fix(browser): Use drift-corrected time origin for INP, replay and profiling#23067

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fix(browser): Use drift-corrected time origin for INP, replay and profiling #23067

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5 changes: 4 additions & 1 deletion packages/browser-utils/src/metrics/webVitalSpans.ts
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Original file line numberDiff line numberDiff line change
@@ -1,6 +1,7 @@
import type { Client, Integration, Span, SpanAttributes } from '@sentry/core';
import {
browserPerformanceTimeOrigin,
correctedPerformanceTimeOrigin,
Comment on lines 3 to +4

@logaretmlogaretmAug 9, 2026

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Do we need both? I don't think we would like to use a non-accurate time origin anywhere, or maybe I misunderstood?

debug,
getActiveSpan,
getClient,
Expand DownExpand Up@@ -329,7 +330,9 @@ export function trackInpAsSpan(client: Client): void {
export function _sendInpSpan(inpValue: number, entry: PerformanceEventTiming, standalone = false): void {
DEBUG_BUILD && debug.log(`Sending INP span (${inpValue})`);

const startTime = msToSec((browserPerformanceTimeOrigin() as number) + entry.startTime);
// INP reports on pagehide, potentially hours after the origin cached at init, so the corrected origin is used to stay
// on the same timeline as span and event timestamps.
const startTime = msToSec((correctedPerformanceTimeOrigin() as number) + entry.startTime);
const duration = msToSec(inpValue);
const interactionType = INP_ENTRY_MAP[entry.name];

Expand Down
3 changes: 3 additions & 0 deletions packages/browser-utils/test/metrics/webVitalSpans.test.ts
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Original file line numberDiff line numberDiff line change
Expand Up@@ -17,6 +17,7 @@ vi.mock('@sentry/core', async () => {
return {
...actual,
browserPerformanceTimeOrigin: vi.fn(),
correctedPerformanceTimeOrigin: vi.fn(),
timestampInSeconds: vi.fn(),
getCurrentScope: vi.fn(),
getClient: vi.fn(),
Expand DownExpand Up@@ -475,6 +476,7 @@ describe('_sendInpSpan', () => {
beforeEach(() => {
vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
vi.mocked(htmlTreeAsString).mockReturnValue('<button>');
vi.mocked(SentryCore.startInactiveSpan).mockReturnValue(mockSpan as any);
vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
Expand DownExpand Up@@ -592,6 +594,7 @@ describe('trackInpAsSpan', () => {

beforeEach(() => {
vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
vi.mocked(SentryCore.startInactiveSpan).mockReturnValue({ end: vi.fn() } as any);
Expand Down
6 changes: 3 additions & 3 deletions packages/browser/src/profiling/utils.ts
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Original file line numberDiff line numberDiff line change
Expand Up@@ -12,7 +12,7 @@ import type {
ThreadCpuProfile,
} from '@sentry/core/browser';
import {
browserPerformanceTimeOrigin,
correctedPerformanceTimeOrigin,
debug,
DEFAULT_ENVIRONMENT,
forEachEnvelopeItem,
Expand DownExpand Up@@ -339,7 +339,7 @@ function convertToContinuousProfile(input: {
}

// Align timestamps to SDK time origin to match span/event timelines
const perfOrigin = browserPerformanceTimeOrigin();
const perfOrigin = correctedPerformanceTimeOrigin();
const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
const adjustForOriginChange = origin - (perfOrigin || origin);

Expand DownExpand Up@@ -412,7 +412,7 @@ export function convertJSSelfProfileToSampledFormat(input: JSSelfProfile): Profi
// when that happens, we need to ensure we are correcting the profile timings so the two timelines stay in sync.
// Since JS self profiling time origin is always initialized to performance.timeOrigin, we need to adjust for
// the drift between the SDK selected value and our profile time origin.
const perfOrigin = browserPerformanceTimeOrigin();
const perfOrigin = correctedPerformanceTimeOrigin();

@cursorcursorBotAug 5, 2026

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Profile elapsed times shift after drift

High Severity

Switching convertJSSelfProfileToSampledFormat to correctedPerformanceTimeOrigin makes adjustForOriginChange non-zero after runtime clock drift. That delta is added into every elapsed_since_start_ns, so the first sample is no longer 0 and all relative sample times shift by the full drift (often negative after device sleep). Continuous profiling absolute timestamps are fine; this only breaks transaction/sampled profiles.

Additional Locations (2)
Fix in CursorFix in Web

Reviewed by Cursor Bugbot for commit 25c1b28. Configure here.

const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
const adjustForOriginChange = origin - (perfOrigin || origin);

Expand Down
7 changes: 6 additions & 1 deletion packages/core/src/shared-exports.ts
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Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -274,7 +274,12 @@ export {
supportsReferrerPolicy,
} from './utils/supports';
export { SyncPromise, rejectedSyncPromise, resolvedSyncPromise } from './utils/syncpromise';
export { browserPerformanceTimeOrigin, dateTimestampInSeconds, timestampInSeconds } from './utils/time';
export {
browserPerformanceTimeOrigin,
correctedPerformanceTimeOrigin,
dateTimestampInSeconds,
timestampInSeconds,
} from './utils/time';
export {
TRACEPARENT_REGEXP,
extractTraceparentData,
Expand Down
24 changes: 22 additions & 2 deletions packages/core/src/utils/time.ts
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Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -31,6 +31,12 @@ export function dateTimestampInSeconds(): number {
return safeDateNow() / ONE_SECOND_IN_MS;
}

/**
* The time origin `timestampInSeconds` currently maps the monotonic clock against, kept in sync with the corrections it
* applies. `undefined` until the first `timestampInSeconds` call, and whenever the Performance API is unavailable.
*/
let _correctedTimeOrigin: number | undefined;

/**
* Returns a wrapper around the native Performance API browser implementation, or undefined for browsers that do not
* support the API.
Expand All@@ -47,7 +53,7 @@ function createUnixTimestampInSecondsFunc(): () => number {

// performance.now() is a monotonic clock, which means it starts at 0 when the process begins. To get the current
// wall clock time (actual UNIX timestamp), we need to add the starting time origin and the current time elapsed.
let timeOrigin = performance.timeOrigin;
let timeOrigin = (_correctedTimeOrigin = performance.timeOrigin);

return () => {
return withRandomSafeContext(() => {
Expand All@@ -66,7 +72,7 @@ function createUnixTimestampInSecondsFunc(): () => number {
// See: https://github.com/mdn/content/issues/4713
// See: https://dev.to/noamr/when-a-millisecond-is-not-a-millisecond-3h6
if (Math.abs(timeOrigin + performanceNow - dateNow) > CLOCK_DRIFT_THRESHOLD_MS) {
timeOrigin = dateNow - performanceNow;
timeOrigin = _correctedTimeOrigin = dateNow - performanceNow;
}

return (timeOrigin + performanceNow) / ONE_SECOND_IN_MS;
Expand All@@ -76,6 +82,20 @@ function createUnixTimestampInSecondsFunc(): () => number {

let _cachedTimestampInSeconds: (() => number) | undefined;

/**
* Returns the time origin (in milliseconds since the UNIX epoch) that {@link timestampInSeconds} currently maps
* `performance.now()` against, including any correction it has applied for clock drift.
*
* Use this over {@link browserPerformanceTimeOrigin} when converting a `PerformanceEntry`'s monotonic `startTime` to
* wall clock time at the moment the entry is observed, so the result shares a timeline with span and event timestamps.
* Returns `undefined` if the Performance API is unavailable, in which case monotonic timestamps cannot be converted.
*/
export function correctedPerformanceTimeOrigin(): number | undefined {
// The origin is only populated once `timestampInSeconds` has resolved which clock source to use.
timestampInSeconds();
return _correctedTimeOrigin;
}

/**
* Returns a timestamp in seconds since the UNIX epoch using either the Performance or Date APIs, depending on the
* availability of the Performance API.
Expand Down
81 changes: 78 additions & 3 deletions packages/core/test/lib/utils/time.test.ts
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Original file line numberDiff line numberDiff line change
Expand Up@@ -9,11 +9,17 @@ async function getFreshPerformanceTimeOrigin() {

let freshImportCounter = 0;

async function getFreshTimestampInSeconds(): Promise<() => number> {
async function getFreshTimeModule(): Promise<{
timestampInSeconds: () => number;
correctedPerformanceTimeOrigin: () => number | undefined;
}> {
// A counter rather than `Date.now()`: these tests run under fake timers, which freeze the wall clock and would
// otherwise hand out a cached module.
const timeModule = await import(`../../../src/utils/time?update=${freshImportCounter++}`);
return timeModule.timestampInSeconds;
return import(`../../../src/utils/time?update=${freshImportCounter++}`);
}

async function getFreshTimestampInSeconds(): Promise<() => number> {
return (await getFreshTimeModule()).timestampInSeconds;
}

const RELIABLE_THRESHOLD_MS = 300_000;
Expand DownExpand Up@@ -180,6 +186,75 @@ describe('timestampInSeconds', () => {
});
});

describe('correctedPerformanceTimeOrigin', () => {
afterEach(() => {
vi.useRealTimers();
vi.unstubAllGlobals();
});

it('returns `performance.timeOrigin` while the clocks agree', async () => {
const currentTimeMs = 1767778040866;
const timeSincePageloadMs = 1_000;
const timeOrigin = currentTimeMs - timeSincePageloadMs;

vi.useFakeTimers();
vi.setSystemTime(new Date(currentTimeMs));
vi.stubGlobal('performance', { timeOrigin, now: () => timeSincePageloadMs });

const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

expect(correctedPerformanceTimeOrigin()).toBe(timeOrigin);
});

it('returns the corrected origin after clock drift, without a prior `timestampInSeconds` call', async () => {
const currentTimeMs = 1767778040866;
const timeSincePageloadMs = 1_000;
const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

vi.useFakeTimers();
vi.setSystemTime(new Date(currentTimeMs));
vi.stubGlobal('performance', {
timeOrigin: currentTimeMs - timeSincePageloadMs,
now: () => timeSincePageloadMs,
});

const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

expect(correctedPerformanceTimeOrigin()).toBe(currentTimeMs + sleepDurationMs - timeSincePageloadMs);
});

it('stays on the same timeline as `timestampInSeconds`', async () => {
const currentTimeMs = 1767778040866;
const timeSincePageloadMs = 1_000;
const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

vi.useFakeTimers();
vi.setSystemTime(new Date(currentTimeMs));
vi.stubGlobal('performance', {
timeOrigin: currentTimeMs - timeSincePageloadMs,
now: () => timeSincePageloadMs,
});

const { correctedPerformanceTimeOrigin, timestampInSeconds } = await getFreshTimeModule();

vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

// Converting the current `performance.now()` against the origin must yield the same wall clock time that
// `timestampInSeconds` reports, otherwise perf entries and spans land on diverging timelines.
expect((correctedPerformanceTimeOrigin() as number) + timeSincePageloadMs).toBe(timestampInSeconds() * 1000);
});

it('returns `undefined` if the performance API is unavailable', async () => {
vi.stubGlobal('performance', undefined);

const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

expect(correctedPerformanceTimeOrigin()).toBeUndefined();
});
});

describe('browserPerformanceTimeOrigin', () => {
it('returns `performance.timeOrigin` if it is available and reliable', async () => {
const timeOrigin = await getFreshPerformanceTimeOrigin();
Expand Down
6 changes: 3 additions & 3 deletions packages/replay-internal/src/util/createPerformanceEntries.ts
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Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
import { browserPerformanceTimeOrigin } from '@sentry/core';
import { correctedPerformanceTimeOrigin } from '@sentry/core';
import { record } from '@sentry/rrweb';
import { WINDOW } from '../constants';
import type {
Expand DownExpand Up@@ -87,9 +87,9 @@ function createPerformanceEntry(entry: AllPerformanceEntry): ReplayPerformanceEn
}

function getAbsoluteTime(time: number): number {
// browserPerformanceTimeOrigin can be undefined if `performance` or
// correctedPerformanceTimeOrigin can be undefined if `performance` or
// `performance.now` doesn't exist, but this is already checked by this integration
return ((browserPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
return ((correctedPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
}

function createPaintEntry(entry: PerformancePaintTiming): ReplayPerformanceEntry<PaintData> {
Expand Down
Loading
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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fix(browser): Use drift-corrected time origin for INP, replay and profiling#23067

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fix(browser): Use drift-corrected time origin for INP, replay and profiling
#23067
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5 changes: 4 additions & 1 deletion
packages/browser-utils/src/metrics/webVitalSpans.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,6 +1,7 @@
import type { Client, Integration, Span, SpanAttributes } from '@sentry/core';
import {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,

Comment on lines

3
 to 
+4

@logaretmlogaretmAug 9, 2026

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Do we need both? I don't think we would like to use a non-accurate time origin anywhere, or maybe I misunderstood?
 debug,
 getActiveSpan,
 getClient,
Expand DownExpand Up@@ -329,7 +330,9 @@ export function trackInpAsSpan(client: Client): void {
export function _sendInpSpan(inpValue: number, entry: PerformanceEventTiming, standalone = false): void {
 DEBUG_BUILD && debug.log(`Sending INP span (${inpValue})`);

 const startTime = msToSec((browserPerformanceTimeOrigin() as number) + entry.startTime);
 // INP reports on pagehide, potentially hours after the origin cached at init, so the corrected origin is used to stay
 // on the same timeline as span and event timestamps.
 const startTime = msToSec((correctedPerformanceTimeOrigin() as number) + entry.startTime);
 const duration = msToSec(inpValue);
 const interactionType = INP_ENTRY_MAP[entry.name];

Expand Down

3 changes: 3 additions & 0 deletions
packages/browser-utils/test/metrics/webVitalSpans.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -17,6 +17,7 @@ vi.mock('@sentry/core', async () => {
 return {
 ...actual,
 browserPerformanceTimeOrigin: vi.fn(),
 correctedPerformanceTimeOrigin: vi.fn(),
 timestampInSeconds: vi.fn(),
 getCurrentScope: vi.fn(),
 getClient: vi.fn(),
Expand DownExpand Up@@ -475,6 +476,7 @@ describe('_sendInpSpan', () => {
 beforeEach(() => {
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(htmlTreeAsString).mockReturnValue('<button>');
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue(mockSpan as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
Expand DownExpand Up@@ -592,6 +594,7 @@ describe('trackInpAsSpan', () => {

 beforeEach(() => {
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue({ end: vi.fn() } as any);
Expand Down

6 changes: 3 additions & 3 deletions
packages/browser/src/profiling/utils.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -12,7 +12,7 @@ import type {
 ThreadCpuProfile,
} from '@sentry/core/browser';
import {
browserPerformanceTimeOrigin,
correctedPerformanceTimeOrigin,
 debug,
 DEFAULT_ENVIRONMENT,
 forEachEnvelopeItem,
Expand DownExpand Up@@ -339,7 +339,7 @@ function convertToContinuousProfile(input: {
 }

 // Align timestamps to SDK time origin to match span/event timelines
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand DownExpand Up@@ -412,7 +412,7 @@ export function convertJSSelfProfileToSampledFormat(input: JSSelfProfile): Profi
 // when that happens, we need to ensure we are correcting the profile timings so the two timelines stay in sync.
 // Since JS self profiling time origin is always initialized to performance.timeOrigin, we need to adjust for
 // the drift between the SDK selected value and our profile time origin.
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
@cursorcursorBotAug 5, 2026

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Profile elapsed times shift after drift
High Severity
Switching convertJSSelfProfileToSampledFormat to correctedPerformanceTimeOrigin makes adjustForOriginChange non-zero after runtime clock drift. That delta is added into every elapsed_since_start_ns, so the first sample is no longer 0 and all relative sample times shift by the full drift (often negative after device sleep). Continuous profiling absolute timestamps are fine; this only breaks transaction/sampled profiles.
Additional Locations (2)
Fix in CursorFix in Web
Reviewed by Cursor Bugbot for commit 25c1b28. Configure here.
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand Down

7 changes: 6 additions & 1 deletion
packages/core/src/shared-exports.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -274,7 +274,12 @@ export {
 supportsReferrerPolicy,
} from './utils/supports';
export { SyncPromise, rejectedSyncPromise, resolvedSyncPromise } from './utils/syncpromise';
export { browserPerformanceTimeOrigin, dateTimestampInSeconds, timestampInSeconds } from './utils/time';
export {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,
 dateTimestampInSeconds,
 timestampInSeconds,
} from './utils/time';
export {
 TRACEPARENT_REGEXP,
 extractTraceparentData,
Expand Down

24 changes: 22 additions & 2 deletions
packages/core/src/utils/time.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -31,6 +31,12 @@ export function dateTimestampInSeconds(): number {
 return safeDateNow() / ONE_SECOND_IN_MS;
}

/**
 * The time origin `timestampInSeconds` currently maps the monotonic clock against, kept in sync with the corrections it
 * applies. `undefined` until the first `timestampInSeconds` call, and whenever the Performance API is unavailable.
 */
let _correctedTimeOrigin: number | undefined;

/**
 * Returns a wrapper around the native Performance API browser implementation, or undefined for browsers that do not
 * support the API.
Expand All@@ -47,7 +53,7 @@ function createUnixTimestampInSecondsFunc(): () => number {

 // performance.now() is a monotonic clock, which means it starts at 0 when the process begins. To get the current
 // wall clock time (actual UNIX timestamp), we need to add the starting time origin and the current time elapsed.
 let timeOrigin = performance.timeOrigin;
 let timeOrigin = (_correctedTimeOrigin = performance.timeOrigin);

 return () => {
 return withRandomSafeContext(() => {
Expand All@@ -66,7 +72,7 @@ function createUnixTimestampInSecondsFunc(): () => number {
 // See: https://github.com/mdn/content/issues/4713
 // See: https://dev.to/noamr/when-a-millisecond-is-not-a-millisecond-3h6
 if (Math.abs(timeOrigin + performanceNow - dateNow) > CLOCK_DRIFT_THRESHOLD_MS) {
 timeOrigin = dateNow - performanceNow;
 timeOrigin = _correctedTimeOrigin = dateNow - performanceNow;
 }

 return (timeOrigin + performanceNow) / ONE_SECOND_IN_MS;
Expand All@@ -76,6 +82,20 @@ function createUnixTimestampInSecondsFunc(): () => number {

let _cachedTimestampInSeconds: (() => number) | undefined;

/**
 * Returns the time origin (in milliseconds since the UNIX epoch) that {@link timestampInSeconds} currently maps
 * `performance.now()` against, including any correction it has applied for clock drift.
 *
 * Use this over {@link browserPerformanceTimeOrigin} when converting a `PerformanceEntry`'s monotonic `startTime` to
 * wall clock time at the moment the entry is observed, so the result shares a timeline with span and event timestamps.
 * Returns `undefined` if the Performance API is unavailable, in which case monotonic timestamps cannot be converted.
 */
export function correctedPerformanceTimeOrigin(): number | undefined {
 // The origin is only populated once `timestampInSeconds` has resolved which clock source to use.
 timestampInSeconds();
 return _correctedTimeOrigin;
}

/**
 * Returns a timestamp in seconds since the UNIX epoch using either the Performance or Date APIs, depending on the
 * availability of the Performance API.
Expand Down

81 changes: 78 additions & 3 deletions
packages/core/test/lib/utils/time.test.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -9,11 +9,17 @@ async function getFreshPerformanceTimeOrigin() {

let freshImportCounter = 0;

async function getFreshTimestampInSeconds(): Promise<() => number> {
async function getFreshTimeModule(): Promise<{
 timestampInSeconds: () => number;
 correctedPerformanceTimeOrigin: () => number | undefined;
}> {
 // A counter rather than `Date.now()`: these tests run under fake timers, which freeze the wall clock and would
 // otherwise hand out a cached module.
 const timeModule = await import(`../../../src/utils/time?update=${freshImportCounter++}`);
 return timeModule.timestampInSeconds;
 return import(`../../../src/utils/time?update=${freshImportCounter++}`);
}

async function getFreshTimestampInSeconds(): Promise<() => number> {
 return (await getFreshTimeModule()).timestampInSeconds;
}

const RELIABLE_THRESHOLD_MS = 300_000;
Expand DownExpand Up@@ -180,6 +186,75 @@ describe('timestampInSeconds', () => {
 });
});

describe('correctedPerformanceTimeOrigin', () => {
 afterEach(() => {
 vi.useRealTimers();
 vi.unstubAllGlobals();
 });

 it('returns `performance.timeOrigin` while the clocks agree', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const timeOrigin = currentTimeMs - timeSincePageloadMs;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', { timeOrigin, now: () => timeSincePageloadMs });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBe(timeOrigin);
 });

 it('returns the corrected origin after clock drift, without a prior `timestampInSeconds` call', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 expect(correctedPerformanceTimeOrigin()).toBe(currentTimeMs + sleepDurationMs - timeSincePageloadMs);
 });

 it('stays on the same timeline as `timestampInSeconds`', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin, timestampInSeconds } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 // Converting the current `performance.now()` against the origin must yield the same wall clock time that
 // `timestampInSeconds` reports, otherwise perf entries and spans land on diverging timelines.
 expect((correctedPerformanceTimeOrigin() as number) + timeSincePageloadMs).toBe(timestampInSeconds() * 1000);
 });

 it('returns `undefined` if the performance API is unavailable', async () => {
 vi.stubGlobal('performance', undefined);

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBeUndefined();
 });
});

describe('browserPerformanceTimeOrigin', () => {
 it('returns `performance.timeOrigin` if it is available and reliable', async () => {
 const timeOrigin = await getFreshPerformanceTimeOrigin();
Expand Down

6 changes: 3 additions & 3 deletions
packages/replay-internal/src/util/createPerformanceEntries.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
import { browserPerformanceTimeOrigin } from '@sentry/core';
import { correctedPerformanceTimeOrigin } from '@sentry/core';
import { record } from '@sentry/rrweb';
import { WINDOW } from '../constants';
import type {
Expand DownExpand Up@@ -87,9 +87,9 @@ function createPerformanceEntry(entry: AllPerformanceEntry): ReplayPerformanceEn
}

function getAbsoluteTime(time: number): number {
 // browserPerformanceTimeOrigin can be undefined if `performance` or
 // correctedPerformanceTimeOrigin can be undefined if `performance` or
 // `performance.now` doesn't exist, but this is already checked by this integration
 return ((browserPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
 return ((correctedPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
}

function createPaintEntry(entry: PerformancePaintTiming): ReplayPerformanceEntry<PaintData> {
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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fix(browser): Use drift-corrected time origin for INP, replay and profiling#23067

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fix(browser): Use drift-corrected time origin for INP, replay and profiling
#23067
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5 changes: 4 additions & 1 deletion
packages/browser-utils/src/metrics/webVitalSpans.ts

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Original file line numberDiff line numberDiff line change
@@ -1,6 +1,7 @@
import type { Client, Integration, Span, SpanAttributes } from '@sentry/core';
import {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,

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3
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+4

@logaretmlogaretmAug 9, 2026

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Do we need both? I don't think we would like to use a non-accurate time origin anywhere, or maybe I misunderstood?
 debug,
 getActiveSpan,
 getClient,
Expand DownExpand Up@@ -329,7 +330,9 @@ export function trackInpAsSpan(client: Client): void {
export function _sendInpSpan(inpValue: number, entry: PerformanceEventTiming, standalone = false): void {
 DEBUG_BUILD && debug.log(`Sending INP span (${inpValue})`);

 const startTime = msToSec((browserPerformanceTimeOrigin() as number) + entry.startTime);
 // INP reports on pagehide, potentially hours after the origin cached at init, so the corrected origin is used to stay
 // on the same timeline as span and event timestamps.
 const startTime = msToSec((correctedPerformanceTimeOrigin() as number) + entry.startTime);
 const duration = msToSec(inpValue);
 const interactionType = INP_ENTRY_MAP[entry.name];

Expand Down

3 changes: 3 additions & 0 deletions
packages/browser-utils/test/metrics/webVitalSpans.test.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -17,6 +17,7 @@ vi.mock('@sentry/core', async () => {
 return {
 ...actual,
 browserPerformanceTimeOrigin: vi.fn(),
 correctedPerformanceTimeOrigin: vi.fn(),
 timestampInSeconds: vi.fn(),
 getCurrentScope: vi.fn(),
 getClient: vi.fn(),
Expand DownExpand Up@@ -475,6 +476,7 @@ describe('_sendInpSpan', () => {
 beforeEach(() => {
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(htmlTreeAsString).mockReturnValue('<button>');
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue(mockSpan as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
Expand DownExpand Up@@ -592,6 +594,7 @@ describe('trackInpAsSpan', () => {

 beforeEach(() => {
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue({ end: vi.fn() } as any);
Expand Down

6 changes: 3 additions & 3 deletions
packages/browser/src/profiling/utils.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -12,7 +12,7 @@ import type {
 ThreadCpuProfile,
} from '@sentry/core/browser';
import {
browserPerformanceTimeOrigin,
correctedPerformanceTimeOrigin,
 debug,
 DEFAULT_ENVIRONMENT,
 forEachEnvelopeItem,
Expand DownExpand Up@@ -339,7 +339,7 @@ function convertToContinuousProfile(input: {
 }

 // Align timestamps to SDK time origin to match span/event timelines
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand DownExpand Up@@ -412,7 +412,7 @@ export function convertJSSelfProfileToSampledFormat(input: JSSelfProfile): Profi
 // when that happens, we need to ensure we are correcting the profile timings so the two timelines stay in sync.
 // Since JS self profiling time origin is always initialized to performance.timeOrigin, we need to adjust for
 // the drift between the SDK selected value and our profile time origin.
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
@cursorcursorBotAug 5, 2026

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Profile elapsed times shift after drift
High Severity
Switching convertJSSelfProfileToSampledFormat to correctedPerformanceTimeOrigin makes adjustForOriginChange non-zero after runtime clock drift. That delta is added into every elapsed_since_start_ns, so the first sample is no longer 0 and all relative sample times shift by the full drift (often negative after device sleep). Continuous profiling absolute timestamps are fine; this only breaks transaction/sampled profiles.
Additional Locations (2)
Fix in CursorFix in Web
Reviewed by Cursor Bugbot for commit 25c1b28. Configure here.
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand Down

7 changes: 6 additions & 1 deletion
packages/core/src/shared-exports.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -274,7 +274,12 @@ export {
 supportsReferrerPolicy,
} from './utils/supports';
export { SyncPromise, rejectedSyncPromise, resolvedSyncPromise } from './utils/syncpromise';
export { browserPerformanceTimeOrigin, dateTimestampInSeconds, timestampInSeconds } from './utils/time';
export {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,
 dateTimestampInSeconds,
 timestampInSeconds,
} from './utils/time';
export {
 TRACEPARENT_REGEXP,
 extractTraceparentData,
Expand Down

24 changes: 22 additions & 2 deletions
packages/core/src/utils/time.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -31,6 +31,12 @@ export function dateTimestampInSeconds(): number {
 return safeDateNow() / ONE_SECOND_IN_MS;
}

/**
 * The time origin `timestampInSeconds` currently maps the monotonic clock against, kept in sync with the corrections it
 * applies. `undefined` until the first `timestampInSeconds` call, and whenever the Performance API is unavailable.
 */
let _correctedTimeOrigin: number | undefined;

/**
 * Returns a wrapper around the native Performance API browser implementation, or undefined for browsers that do not
 * support the API.
Expand All@@ -47,7 +53,7 @@ function createUnixTimestampInSecondsFunc(): () => number {

 // performance.now() is a monotonic clock, which means it starts at 0 when the process begins. To get the current
 // wall clock time (actual UNIX timestamp), we need to add the starting time origin and the current time elapsed.
 let timeOrigin = performance.timeOrigin;
 let timeOrigin = (_correctedTimeOrigin = performance.timeOrigin);

 return () => {
 return withRandomSafeContext(() => {
Expand All@@ -66,7 +72,7 @@ function createUnixTimestampInSecondsFunc(): () => number {
 // See: https://github.com/mdn/content/issues/4713
 // See: https://dev.to/noamr/when-a-millisecond-is-not-a-millisecond-3h6
 if (Math.abs(timeOrigin + performanceNow - dateNow) > CLOCK_DRIFT_THRESHOLD_MS) {
 timeOrigin = dateNow - performanceNow;
 timeOrigin = _correctedTimeOrigin = dateNow - performanceNow;
 }

 return (timeOrigin + performanceNow) / ONE_SECOND_IN_MS;
Expand All@@ -76,6 +82,20 @@ function createUnixTimestampInSecondsFunc(): () => number {

let _cachedTimestampInSeconds: (() => number) | undefined;

/**
 * Returns the time origin (in milliseconds since the UNIX epoch) that {@link timestampInSeconds} currently maps
 * `performance.now()` against, including any correction it has applied for clock drift.
 *
 * Use this over {@link browserPerformanceTimeOrigin} when converting a `PerformanceEntry`'s monotonic `startTime` to
 * wall clock time at the moment the entry is observed, so the result shares a timeline with span and event timestamps.
 * Returns `undefined` if the Performance API is unavailable, in which case monotonic timestamps cannot be converted.
 */
export function correctedPerformanceTimeOrigin(): number | undefined {
 // The origin is only populated once `timestampInSeconds` has resolved which clock source to use.
 timestampInSeconds();
 return _correctedTimeOrigin;
}

/**
 * Returns a timestamp in seconds since the UNIX epoch using either the Performance or Date APIs, depending on the
 * availability of the Performance API.
Expand Down

81 changes: 78 additions & 3 deletions
packages/core/test/lib/utils/time.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -9,11 +9,17 @@ async function getFreshPerformanceTimeOrigin() {

let freshImportCounter = 0;

async function getFreshTimestampInSeconds(): Promise<() => number> {
async function getFreshTimeModule(): Promise<{
 timestampInSeconds: () => number;
 correctedPerformanceTimeOrigin: () => number | undefined;
}> {
 // A counter rather than `Date.now()`: these tests run under fake timers, which freeze the wall clock and would
 // otherwise hand out a cached module.
 const timeModule = await import(`../../../src/utils/time?update=${freshImportCounter++}`);
 return timeModule.timestampInSeconds;
 return import(`../../../src/utils/time?update=${freshImportCounter++}`);
}

async function getFreshTimestampInSeconds(): Promise<() => number> {
 return (await getFreshTimeModule()).timestampInSeconds;
}

const RELIABLE_THRESHOLD_MS = 300_000;
Expand DownExpand Up@@ -180,6 +186,75 @@ describe('timestampInSeconds', () => {
 });
});

describe('correctedPerformanceTimeOrigin', () => {
 afterEach(() => {
 vi.useRealTimers();
 vi.unstubAllGlobals();
 });

 it('returns `performance.timeOrigin` while the clocks agree', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const timeOrigin = currentTimeMs - timeSincePageloadMs;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', { timeOrigin, now: () => timeSincePageloadMs });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBe(timeOrigin);
 });

 it('returns the corrected origin after clock drift, without a prior `timestampInSeconds` call', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 expect(correctedPerformanceTimeOrigin()).toBe(currentTimeMs + sleepDurationMs - timeSincePageloadMs);
 });

 it('stays on the same timeline as `timestampInSeconds`', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin, timestampInSeconds } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 // Converting the current `performance.now()` against the origin must yield the same wall clock time that
 // `timestampInSeconds` reports, otherwise perf entries and spans land on diverging timelines.
 expect((correctedPerformanceTimeOrigin() as number) + timeSincePageloadMs).toBe(timestampInSeconds() * 1000);
 });

 it('returns `undefined` if the performance API is unavailable', async () => {
 vi.stubGlobal('performance', undefined);

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBeUndefined();
 });
});

describe('browserPerformanceTimeOrigin', () => {
 it('returns `performance.timeOrigin` if it is available and reliable', async () => {
 const timeOrigin = await getFreshPerformanceTimeOrigin();
Expand Down

6 changes: 3 additions & 3 deletions
packages/replay-internal/src/util/createPerformanceEntries.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
import { browserPerformanceTimeOrigin } from '@sentry/core';
import { correctedPerformanceTimeOrigin } from '@sentry/core';
import { record } from '@sentry/rrweb';
import { WINDOW } from '../constants';
import type {
Expand DownExpand Up@@ -87,9 +87,9 @@ function createPerformanceEntry(entry: AllPerformanceEntry): ReplayPerformanceEn
}

function getAbsoluteTime(time: number): number {
 // browserPerformanceTimeOrigin can be undefined if `performance` or
 // correctedPerformanceTimeOrigin can be undefined if `performance` or
 // `performance.now` doesn't exist, but this is already checked by this integration
 return ((browserPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
 return ((correctedPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
}

function createPaintEntry(entry: PerformancePaintTiming): ReplayPerformanceEntry<PaintData> {
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(browser): Use drift-corrected time origin for INP, replay and profiling#23067

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fix(browser): Use drift-corrected time origin for INP, replay and profiling
#23067
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5 changes: 4 additions & 1 deletion
packages/browser-utils/src/metrics/webVitalSpans.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,6 +1,7 @@
import type { Client, Integration, Span, SpanAttributes } from '@sentry/core';
import {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,

Comment on lines

3
 to 
+4

@logaretmlogaretmAug 9, 2026

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Do we need both? I don't think we would like to use a non-accurate time origin anywhere, or maybe I misunderstood?
 debug,
 getActiveSpan,
 getClient,
Expand DownExpand Up@@ -329,7 +330,9 @@ export function trackInpAsSpan(client: Client): void {
export function _sendInpSpan(inpValue: number, entry: PerformanceEventTiming, standalone = false): void {
 DEBUG_BUILD && debug.log(`Sending INP span (${inpValue})`);

 const startTime = msToSec((browserPerformanceTimeOrigin() as number) + entry.startTime);
 // INP reports on pagehide, potentially hours after the origin cached at init, so the corrected origin is used to stay
 // on the same timeline as span and event timestamps.
 const startTime = msToSec((correctedPerformanceTimeOrigin() as number) + entry.startTime);
 const duration = msToSec(inpValue);
 const interactionType = INP_ENTRY_MAP[entry.name];

Expand Down

3 changes: 3 additions & 0 deletions
packages/browser-utils/test/metrics/webVitalSpans.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -17,6 +17,7 @@ vi.mock('@sentry/core', async () => {
 return {
 ...actual,
 browserPerformanceTimeOrigin: vi.fn(),
 correctedPerformanceTimeOrigin: vi.fn(),
 timestampInSeconds: vi.fn(),
 getCurrentScope: vi.fn(),
 getClient: vi.fn(),
Expand DownExpand Up@@ -475,6 +476,7 @@ describe('_sendInpSpan', () => {
 beforeEach(() => {
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(htmlTreeAsString).mockReturnValue('<button>');
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue(mockSpan as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
Expand DownExpand Up@@ -592,6 +594,7 @@ describe('trackInpAsSpan', () => {

 beforeEach(() => {
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue({ end: vi.fn() } as any);
Expand Down

6 changes: 3 additions & 3 deletions
packages/browser/src/profiling/utils.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -12,7 +12,7 @@ import type {
 ThreadCpuProfile,
} from '@sentry/core/browser';
import {
browserPerformanceTimeOrigin,
correctedPerformanceTimeOrigin,
 debug,
 DEFAULT_ENVIRONMENT,
 forEachEnvelopeItem,
Expand DownExpand Up@@ -339,7 +339,7 @@ function convertToContinuousProfile(input: {
 }

 // Align timestamps to SDK time origin to match span/event timelines
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand DownExpand Up@@ -412,7 +412,7 @@ export function convertJSSelfProfileToSampledFormat(input: JSSelfProfile): Profi
 // when that happens, we need to ensure we are correcting the profile timings so the two timelines stay in sync.
 // Since JS self profiling time origin is always initialized to performance.timeOrigin, we need to adjust for
 // the drift between the SDK selected value and our profile time origin.
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
@cursorcursorBotAug 5, 2026

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Profile elapsed times shift after drift
High Severity
Switching convertJSSelfProfileToSampledFormat to correctedPerformanceTimeOrigin makes adjustForOriginChange non-zero after runtime clock drift. That delta is added into every elapsed_since_start_ns, so the first sample is no longer 0 and all relative sample times shift by the full drift (often negative after device sleep). Continuous profiling absolute timestamps are fine; this only breaks transaction/sampled profiles.
Additional Locations (2)
Fix in CursorFix in Web
Reviewed by Cursor Bugbot for commit 25c1b28. Configure here.
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand Down

7 changes: 6 additions & 1 deletion
packages/core/src/shared-exports.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -274,7 +274,12 @@ export {
 supportsReferrerPolicy,
} from './utils/supports';
export { SyncPromise, rejectedSyncPromise, resolvedSyncPromise } from './utils/syncpromise';
export { browserPerformanceTimeOrigin, dateTimestampInSeconds, timestampInSeconds } from './utils/time';
export {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,
 dateTimestampInSeconds,
 timestampInSeconds,
} from './utils/time';
export {
 TRACEPARENT_REGEXP,
 extractTraceparentData,
Expand Down

24 changes: 22 additions & 2 deletions
packages/core/src/utils/time.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -31,6 +31,12 @@ export function dateTimestampInSeconds(): number {
 return safeDateNow() / ONE_SECOND_IN_MS;
}

/**
 * The time origin `timestampInSeconds` currently maps the monotonic clock against, kept in sync with the corrections it
 * applies. `undefined` until the first `timestampInSeconds` call, and whenever the Performance API is unavailable.
 */
let _correctedTimeOrigin: number | undefined;

/**
 * Returns a wrapper around the native Performance API browser implementation, or undefined for browsers that do not
 * support the API.
Expand All@@ -47,7 +53,7 @@ function createUnixTimestampInSecondsFunc(): () => number {

 // performance.now() is a monotonic clock, which means it starts at 0 when the process begins. To get the current
 // wall clock time (actual UNIX timestamp), we need to add the starting time origin and the current time elapsed.
 let timeOrigin = performance.timeOrigin;
 let timeOrigin = (_correctedTimeOrigin = performance.timeOrigin);

 return () => {
 return withRandomSafeContext(() => {
Expand All@@ -66,7 +72,7 @@ function createUnixTimestampInSecondsFunc(): () => number {
 // See: https://github.com/mdn/content/issues/4713
 // See: https://dev.to/noamr/when-a-millisecond-is-not-a-millisecond-3h6
 if (Math.abs(timeOrigin + performanceNow - dateNow) > CLOCK_DRIFT_THRESHOLD_MS) {
 timeOrigin = dateNow - performanceNow;
 timeOrigin = _correctedTimeOrigin = dateNow - performanceNow;
 }

 return (timeOrigin + performanceNow) / ONE_SECOND_IN_MS;
Expand All@@ -76,6 +82,20 @@ function createUnixTimestampInSecondsFunc(): () => number {

let _cachedTimestampInSeconds: (() => number) | undefined;

/**
 * Returns the time origin (in milliseconds since the UNIX epoch) that {@link timestampInSeconds} currently maps
 * `performance.now()` against, including any correction it has applied for clock drift.
 *
 * Use this over {@link browserPerformanceTimeOrigin} when converting a `PerformanceEntry`'s monotonic `startTime` to
 * wall clock time at the moment the entry is observed, so the result shares a timeline with span and event timestamps.
 * Returns `undefined` if the Performance API is unavailable, in which case monotonic timestamps cannot be converted.
 */
export function correctedPerformanceTimeOrigin(): number | undefined {
 // The origin is only populated once `timestampInSeconds` has resolved which clock source to use.
 timestampInSeconds();
 return _correctedTimeOrigin;
}

/**
 * Returns a timestamp in seconds since the UNIX epoch using either the Performance or Date APIs, depending on the
 * availability of the Performance API.
Expand Down

81 changes: 78 additions & 3 deletions
packages/core/test/lib/utils/time.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -9,11 +9,17 @@ async function getFreshPerformanceTimeOrigin() {

let freshImportCounter = 0;

async function getFreshTimestampInSeconds(): Promise<() => number> {
async function getFreshTimeModule(): Promise<{
 timestampInSeconds: () => number;
 correctedPerformanceTimeOrigin: () => number | undefined;
}> {
 // A counter rather than `Date.now()`: these tests run under fake timers, which freeze the wall clock and would
 // otherwise hand out a cached module.
 const timeModule = await import(`../../../src/utils/time?update=${freshImportCounter++}`);
 return timeModule.timestampInSeconds;
 return import(`../../../src/utils/time?update=${freshImportCounter++}`);
}

async function getFreshTimestampInSeconds(): Promise<() => number> {
 return (await getFreshTimeModule()).timestampInSeconds;
}

const RELIABLE_THRESHOLD_MS = 300_000;
Expand DownExpand Up@@ -180,6 +186,75 @@ describe('timestampInSeconds', () => {
 });
});

describe('correctedPerformanceTimeOrigin', () => {
 afterEach(() => {
 vi.useRealTimers();
 vi.unstubAllGlobals();
 });

 it('returns `performance.timeOrigin` while the clocks agree', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const timeOrigin = currentTimeMs - timeSincePageloadMs;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', { timeOrigin, now: () => timeSincePageloadMs });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBe(timeOrigin);
 });

 it('returns the corrected origin after clock drift, without a prior `timestampInSeconds` call', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 expect(correctedPerformanceTimeOrigin()).toBe(currentTimeMs + sleepDurationMs - timeSincePageloadMs);
 });

 it('stays on the same timeline as `timestampInSeconds`', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin, timestampInSeconds } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 // Converting the current `performance.now()` against the origin must yield the same wall clock time that
 // `timestampInSeconds` reports, otherwise perf entries and spans land on diverging timelines.
 expect((correctedPerformanceTimeOrigin() as number) + timeSincePageloadMs).toBe(timestampInSeconds() * 1000);
 });

 it('returns `undefined` if the performance API is unavailable', async () => {
 vi.stubGlobal('performance', undefined);

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBeUndefined();
 });
});

describe('browserPerformanceTimeOrigin', () => {
 it('returns `performance.timeOrigin` if it is available and reliable', async () => {
 const timeOrigin = await getFreshPerformanceTimeOrigin();
Expand Down

6 changes: 3 additions & 3 deletions
packages/replay-internal/src/util/createPerformanceEntries.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
import { browserPerformanceTimeOrigin } from '@sentry/core';
import { correctedPerformanceTimeOrigin } from '@sentry/core';
import { record } from '@sentry/rrweb';
import { WINDOW } from '../constants';
import type {
Expand DownExpand Up@@ -87,9 +87,9 @@ function createPerformanceEntry(entry: AllPerformanceEntry): ReplayPerformanceEn
}

function getAbsoluteTime(time: number): number {
 // browserPerformanceTimeOrigin can be undefined if `performance` or
 // correctedPerformanceTimeOrigin can be undefined if `performance` or
 // `performance.now` doesn't exist, but this is already checked by this integration
 return ((browserPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
 return ((correctedPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
}

function createPaintEntry(entry: PerformancePaintTiming): ReplayPerformanceEntry<PaintData> {
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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fix(browser): Use drift-corrected time origin for INP, replay and profiling#23067

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fix(browser): Use drift-corrected time origin for INP, replay and profiling
#23067
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5 changes: 4 additions & 1 deletion
packages/browser-utils/src/metrics/webVitalSpans.ts

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Original file line numberDiff line numberDiff line change
@@ -1,6 +1,7 @@
import type { Client, Integration, Span, SpanAttributes } from '@sentry/core';
import {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,

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3
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+4

@logaretmlogaretmAug 9, 2026

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Do we need both? I don't think we would like to use a non-accurate time origin anywhere, or maybe I misunderstood?
 debug,
 getActiveSpan,
 getClient,
Expand DownExpand Up@@ -329,7 +330,9 @@ export function trackInpAsSpan(client: Client): void {
export function _sendInpSpan(inpValue: number, entry: PerformanceEventTiming, standalone = false): void {
 DEBUG_BUILD && debug.log(`Sending INP span (${inpValue})`);

 const startTime = msToSec((browserPerformanceTimeOrigin() as number) + entry.startTime);
 // INP reports on pagehide, potentially hours after the origin cached at init, so the corrected origin is used to stay
 // on the same timeline as span and event timestamps.
 const startTime = msToSec((correctedPerformanceTimeOrigin() as number) + entry.startTime);
 const duration = msToSec(inpValue);
 const interactionType = INP_ENTRY_MAP[entry.name];

Expand Down

3 changes: 3 additions & 0 deletions
packages/browser-utils/test/metrics/webVitalSpans.test.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -17,6 +17,7 @@ vi.mock('@sentry/core', async () => {
 return {
 ...actual,
 browserPerformanceTimeOrigin: vi.fn(),
 correctedPerformanceTimeOrigin: vi.fn(),
 timestampInSeconds: vi.fn(),
 getCurrentScope: vi.fn(),
 getClient: vi.fn(),
Expand DownExpand Up@@ -475,6 +476,7 @@ describe('_sendInpSpan', () => {
 beforeEach(() => {
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(htmlTreeAsString).mockReturnValue('<button>');
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue(mockSpan as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
Expand DownExpand Up@@ -592,6 +594,7 @@ describe('trackInpAsSpan', () => {

 beforeEach(() => {
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue({ end: vi.fn() } as any);
Expand Down

6 changes: 3 additions & 3 deletions
packages/browser/src/profiling/utils.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -12,7 +12,7 @@ import type {
 ThreadCpuProfile,
} from '@sentry/core/browser';
import {
browserPerformanceTimeOrigin,
correctedPerformanceTimeOrigin,
 debug,
 DEFAULT_ENVIRONMENT,
 forEachEnvelopeItem,
Expand DownExpand Up@@ -339,7 +339,7 @@ function convertToContinuousProfile(input: {
 }

 // Align timestamps to SDK time origin to match span/event timelines
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand DownExpand Up@@ -412,7 +412,7 @@ export function convertJSSelfProfileToSampledFormat(input: JSSelfProfile): Profi
 // when that happens, we need to ensure we are correcting the profile timings so the two timelines stay in sync.
 // Since JS self profiling time origin is always initialized to performance.timeOrigin, we need to adjust for
 // the drift between the SDK selected value and our profile time origin.
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
@cursorcursorBotAug 5, 2026

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Profile elapsed times shift after drift
High Severity
Switching convertJSSelfProfileToSampledFormat to correctedPerformanceTimeOrigin makes adjustForOriginChange non-zero after runtime clock drift. That delta is added into every elapsed_since_start_ns, so the first sample is no longer 0 and all relative sample times shift by the full drift (often negative after device sleep). Continuous profiling absolute timestamps are fine; this only breaks transaction/sampled profiles.
Additional Locations (2)
Fix in CursorFix in Web
Reviewed by Cursor Bugbot for commit 25c1b28. Configure here.
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand Down

7 changes: 6 additions & 1 deletion
packages/core/src/shared-exports.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -274,7 +274,12 @@ export {
 supportsReferrerPolicy,
} from './utils/supports';
export { SyncPromise, rejectedSyncPromise, resolvedSyncPromise } from './utils/syncpromise';
export { browserPerformanceTimeOrigin, dateTimestampInSeconds, timestampInSeconds } from './utils/time';
export {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,
 dateTimestampInSeconds,
 timestampInSeconds,
} from './utils/time';
export {
 TRACEPARENT_REGEXP,
 extractTraceparentData,
Expand Down

24 changes: 22 additions & 2 deletions
packages/core/src/utils/time.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -31,6 +31,12 @@ export function dateTimestampInSeconds(): number {
 return safeDateNow() / ONE_SECOND_IN_MS;
}

/**
 * The time origin `timestampInSeconds` currently maps the monotonic clock against, kept in sync with the corrections it
 * applies. `undefined` until the first `timestampInSeconds` call, and whenever the Performance API is unavailable.
 */
let _correctedTimeOrigin: number | undefined;

/**
 * Returns a wrapper around the native Performance API browser implementation, or undefined for browsers that do not
 * support the API.
Expand All@@ -47,7 +53,7 @@ function createUnixTimestampInSecondsFunc(): () => number {

 // performance.now() is a monotonic clock, which means it starts at 0 when the process begins. To get the current
 // wall clock time (actual UNIX timestamp), we need to add the starting time origin and the current time elapsed.
 let timeOrigin = performance.timeOrigin;
 let timeOrigin = (_correctedTimeOrigin = performance.timeOrigin);

 return () => {
 return withRandomSafeContext(() => {
Expand All@@ -66,7 +72,7 @@ function createUnixTimestampInSecondsFunc(): () => number {
 // See: https://github.com/mdn/content/issues/4713
 // See: https://dev.to/noamr/when-a-millisecond-is-not-a-millisecond-3h6
 if (Math.abs(timeOrigin + performanceNow - dateNow) > CLOCK_DRIFT_THRESHOLD_MS) {
 timeOrigin = dateNow - performanceNow;
 timeOrigin = _correctedTimeOrigin = dateNow - performanceNow;
 }

 return (timeOrigin + performanceNow) / ONE_SECOND_IN_MS;
Expand All@@ -76,6 +82,20 @@ function createUnixTimestampInSecondsFunc(): () => number {

let _cachedTimestampInSeconds: (() => number) | undefined;

/**
 * Returns the time origin (in milliseconds since the UNIX epoch) that {@link timestampInSeconds} currently maps
 * `performance.now()` against, including any correction it has applied for clock drift.
 *
 * Use this over {@link browserPerformanceTimeOrigin} when converting a `PerformanceEntry`'s monotonic `startTime` to
 * wall clock time at the moment the entry is observed, so the result shares a timeline with span and event timestamps.
 * Returns `undefined` if the Performance API is unavailable, in which case monotonic timestamps cannot be converted.
 */
export function correctedPerformanceTimeOrigin(): number | undefined {
 // The origin is only populated once `timestampInSeconds` has resolved which clock source to use.
 timestampInSeconds();
 return _correctedTimeOrigin;
}

/**
 * Returns a timestamp in seconds since the UNIX epoch using either the Performance or Date APIs, depending on the
 * availability of the Performance API.
Expand Down

81 changes: 78 additions & 3 deletions
packages/core/test/lib/utils/time.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -9,11 +9,17 @@ async function getFreshPerformanceTimeOrigin() {

let freshImportCounter = 0;

async function getFreshTimestampInSeconds(): Promise<() => number> {
async function getFreshTimeModule(): Promise<{
 timestampInSeconds: () => number;
 correctedPerformanceTimeOrigin: () => number | undefined;
}> {
 // A counter rather than `Date.now()`: these tests run under fake timers, which freeze the wall clock and would
 // otherwise hand out a cached module.
 const timeModule = await import(`../../../src/utils/time?update=${freshImportCounter++}`);
 return timeModule.timestampInSeconds;
 return import(`../../../src/utils/time?update=${freshImportCounter++}`);
}

async function getFreshTimestampInSeconds(): Promise<() => number> {
 return (await getFreshTimeModule()).timestampInSeconds;
}

const RELIABLE_THRESHOLD_MS = 300_000;
Expand DownExpand Up@@ -180,6 +186,75 @@ describe('timestampInSeconds', () => {
 });
});

describe('correctedPerformanceTimeOrigin', () => {
 afterEach(() => {
 vi.useRealTimers();
 vi.unstubAllGlobals();
 });

 it('returns `performance.timeOrigin` while the clocks agree', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const timeOrigin = currentTimeMs - timeSincePageloadMs;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', { timeOrigin, now: () => timeSincePageloadMs });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBe(timeOrigin);
 });

 it('returns the corrected origin after clock drift, without a prior `timestampInSeconds` call', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 expect(correctedPerformanceTimeOrigin()).toBe(currentTimeMs + sleepDurationMs - timeSincePageloadMs);
 });

 it('stays on the same timeline as `timestampInSeconds`', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin, timestampInSeconds } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 // Converting the current `performance.now()` against the origin must yield the same wall clock time that
 // `timestampInSeconds` reports, otherwise perf entries and spans land on diverging timelines.
 expect((correctedPerformanceTimeOrigin() as number) + timeSincePageloadMs).toBe(timestampInSeconds() * 1000);
 });

 it('returns `undefined` if the performance API is unavailable', async () => {
 vi.stubGlobal('performance', undefined);

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBeUndefined();
 });
});

describe('browserPerformanceTimeOrigin', () => {
 it('returns `performance.timeOrigin` if it is available and reliable', async () => {
 const timeOrigin = await getFreshPerformanceTimeOrigin();
Expand Down

6 changes: 3 additions & 3 deletions
packages/replay-internal/src/util/createPerformanceEntries.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
import { browserPerformanceTimeOrigin } from '@sentry/core';
import { correctedPerformanceTimeOrigin } from '@sentry/core';
import { record } from '@sentry/rrweb';
import { WINDOW } from '../constants';
import type {
Expand DownExpand Up@@ -87,9 +87,9 @@ function createPerformanceEntry(entry: AllPerformanceEntry): ReplayPerformanceEn
}

function getAbsoluteTime(time: number): number {
 // browserPerformanceTimeOrigin can be undefined if `performance` or
 // correctedPerformanceTimeOrigin can be undefined if `performance` or
 // `performance.now` doesn't exist, but this is already checked by this integration
 return ((browserPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
 return ((correctedPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
}

function createPaintEntry(entry: PerformancePaintTiming): ReplayPerformanceEntry<PaintData> {
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(browser): Use drift-corrected time origin for INP, replay and profiling#23067

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Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

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Lms24
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fix(browser): Use drift-corrected time origin for INP, replay and profiling
#23067
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5 changes: 4 additions & 1 deletion
packages/browser-utils/src/metrics/webVitalSpans.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,6 +1,7 @@
import type { Client, Integration, Span, SpanAttributes } from '@sentry/core';
import {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,

Comment on lines

3
 to 
+4

@logaretmlogaretmAug 9, 2026

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Do we need both? I don't think we would like to use a non-accurate time origin anywhere, or maybe I misunderstood?
 debug,
 getActiveSpan,
 getClient,
Expand DownExpand Up@@ -329,7 +330,9 @@ export function trackInpAsSpan(client: Client): void {
export function _sendInpSpan(inpValue: number, entry: PerformanceEventTiming, standalone = false): void {
 DEBUG_BUILD && debug.log(`Sending INP span (${inpValue})`);

 const startTime = msToSec((browserPerformanceTimeOrigin() as number) + entry.startTime);
 // INP reports on pagehide, potentially hours after the origin cached at init, so the corrected origin is used to stay
 // on the same timeline as span and event timestamps.
 const startTime = msToSec((correctedPerformanceTimeOrigin() as number) + entry.startTime);
 const duration = msToSec(inpValue);
 const interactionType = INP_ENTRY_MAP[entry.name];

Expand Down

3 changes: 3 additions & 0 deletions
packages/browser-utils/test/metrics/webVitalSpans.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -17,6 +17,7 @@ vi.mock('@sentry/core', async () => {
 return {
 ...actual,
 browserPerformanceTimeOrigin: vi.fn(),
 correctedPerformanceTimeOrigin: vi.fn(),
 timestampInSeconds: vi.fn(),
 getCurrentScope: vi.fn(),
 getClient: vi.fn(),
Expand DownExpand Up@@ -475,6 +476,7 @@ describe('_sendInpSpan', () => {
 beforeEach(() => {
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(htmlTreeAsString).mockReturnValue('<button>');
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue(mockSpan as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
Expand DownExpand Up@@ -592,6 +594,7 @@ describe('trackInpAsSpan', () => {

 beforeEach(() => {
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue({ end: vi.fn() } as any);
Expand Down

6 changes: 3 additions & 3 deletions
packages/browser/src/profiling/utils.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -12,7 +12,7 @@ import type {
 ThreadCpuProfile,
} from '@sentry/core/browser';
import {
browserPerformanceTimeOrigin,
correctedPerformanceTimeOrigin,
 debug,
 DEFAULT_ENVIRONMENT,
 forEachEnvelopeItem,
Expand DownExpand Up@@ -339,7 +339,7 @@ function convertToContinuousProfile(input: {
 }

 // Align timestamps to SDK time origin to match span/event timelines
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand DownExpand Up@@ -412,7 +412,7 @@ export function convertJSSelfProfileToSampledFormat(input: JSSelfProfile): Profi
 // when that happens, we need to ensure we are correcting the profile timings so the two timelines stay in sync.
 // Since JS self profiling time origin is always initialized to performance.timeOrigin, we need to adjust for
 // the drift between the SDK selected value and our profile time origin.
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
@cursorcursorBotAug 5, 2026

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Profile elapsed times shift after drift
High Severity
Switching convertJSSelfProfileToSampledFormat to correctedPerformanceTimeOrigin makes adjustForOriginChange non-zero after runtime clock drift. That delta is added into every elapsed_since_start_ns, so the first sample is no longer 0 and all relative sample times shift by the full drift (often negative after device sleep). Continuous profiling absolute timestamps are fine; this only breaks transaction/sampled profiles.
Additional Locations (2)
Fix in CursorFix in Web
Reviewed by Cursor Bugbot for commit 25c1b28. Configure here.
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand Down

7 changes: 6 additions & 1 deletion
packages/core/src/shared-exports.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -274,7 +274,12 @@ export {
 supportsReferrerPolicy,
} from './utils/supports';
export { SyncPromise, rejectedSyncPromise, resolvedSyncPromise } from './utils/syncpromise';
export { browserPerformanceTimeOrigin, dateTimestampInSeconds, timestampInSeconds } from './utils/time';
export {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,
 dateTimestampInSeconds,
 timestampInSeconds,
} from './utils/time';
export {
 TRACEPARENT_REGEXP,
 extractTraceparentData,
Expand Down

24 changes: 22 additions & 2 deletions
packages/core/src/utils/time.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -31,6 +31,12 @@ export function dateTimestampInSeconds(): number {
 return safeDateNow() / ONE_SECOND_IN_MS;
}

/**
 * The time origin `timestampInSeconds` currently maps the monotonic clock against, kept in sync with the corrections it
 * applies. `undefined` until the first `timestampInSeconds` call, and whenever the Performance API is unavailable.
 */
let _correctedTimeOrigin: number | undefined;

/**
 * Returns a wrapper around the native Performance API browser implementation, or undefined for browsers that do not
 * support the API.
Expand All@@ -47,7 +53,7 @@ function createUnixTimestampInSecondsFunc(): () => number {

 // performance.now() is a monotonic clock, which means it starts at 0 when the process begins. To get the current
 // wall clock time (actual UNIX timestamp), we need to add the starting time origin and the current time elapsed.
 let timeOrigin = performance.timeOrigin;
 let timeOrigin = (_correctedTimeOrigin = performance.timeOrigin);

 return () => {
 return withRandomSafeContext(() => {
Expand All@@ -66,7 +72,7 @@ function createUnixTimestampInSecondsFunc(): () => number {
 // See: https://github.com/mdn/content/issues/4713
 // See: https://dev.to/noamr/when-a-millisecond-is-not-a-millisecond-3h6
 if (Math.abs(timeOrigin + performanceNow - dateNow) > CLOCK_DRIFT_THRESHOLD_MS) {
 timeOrigin = dateNow - performanceNow;
 timeOrigin = _correctedTimeOrigin = dateNow - performanceNow;
 }

 return (timeOrigin + performanceNow) / ONE_SECOND_IN_MS;
Expand All@@ -76,6 +82,20 @@ function createUnixTimestampInSecondsFunc(): () => number {

let _cachedTimestampInSeconds: (() => number) | undefined;

/**
 * Returns the time origin (in milliseconds since the UNIX epoch) that {@link timestampInSeconds} currently maps
 * `performance.now()` against, including any correction it has applied for clock drift.
 *
 * Use this over {@link browserPerformanceTimeOrigin} when converting a `PerformanceEntry`'s monotonic `startTime` to
 * wall clock time at the moment the entry is observed, so the result shares a timeline with span and event timestamps.
 * Returns `undefined` if the Performance API is unavailable, in which case monotonic timestamps cannot be converted.
 */
export function correctedPerformanceTimeOrigin(): number | undefined {
 // The origin is only populated once `timestampInSeconds` has resolved which clock source to use.
 timestampInSeconds();
 return _correctedTimeOrigin;
}

/**
 * Returns a timestamp in seconds since the UNIX epoch using either the Performance or Date APIs, depending on the
 * availability of the Performance API.
Expand Down

81 changes: 78 additions & 3 deletions
packages/core/test/lib/utils/time.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -9,11 +9,17 @@ async function getFreshPerformanceTimeOrigin() {

let freshImportCounter = 0;

async function getFreshTimestampInSeconds(): Promise<() => number> {
async function getFreshTimeModule(): Promise<{
 timestampInSeconds: () => number;
 correctedPerformanceTimeOrigin: () => number | undefined;
}> {
 // A counter rather than `Date.now()`: these tests run under fake timers, which freeze the wall clock and would
 // otherwise hand out a cached module.
 const timeModule = await import(`../../../src/utils/time?update=${freshImportCounter++}`);
 return timeModule.timestampInSeconds;
 return import(`../../../src/utils/time?update=${freshImportCounter++}`);
}

async function getFreshTimestampInSeconds(): Promise<() => number> {
 return (await getFreshTimeModule()).timestampInSeconds;
}

const RELIABLE_THRESHOLD_MS = 300_000;
Expand DownExpand Up@@ -180,6 +186,75 @@ describe('timestampInSeconds', () => {
 });
});

describe('correctedPerformanceTimeOrigin', () => {
 afterEach(() => {
 vi.useRealTimers();
 vi.unstubAllGlobals();
 });

 it('returns `performance.timeOrigin` while the clocks agree', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const timeOrigin = currentTimeMs - timeSincePageloadMs;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', { timeOrigin, now: () => timeSincePageloadMs });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBe(timeOrigin);
 });

 it('returns the corrected origin after clock drift, without a prior `timestampInSeconds` call', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 expect(correctedPerformanceTimeOrigin()).toBe(currentTimeMs + sleepDurationMs - timeSincePageloadMs);
 });

 it('stays on the same timeline as `timestampInSeconds`', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin, timestampInSeconds } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 // Converting the current `performance.now()` against the origin must yield the same wall clock time that
 // `timestampInSeconds` reports, otherwise perf entries and spans land on diverging timelines.
 expect((correctedPerformanceTimeOrigin() as number) + timeSincePageloadMs).toBe(timestampInSeconds() * 1000);
 });

 it('returns `undefined` if the performance API is unavailable', async () => {
 vi.stubGlobal('performance', undefined);

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBeUndefined();
 });
});

describe('browserPerformanceTimeOrigin', () => {
 it('returns `performance.timeOrigin` if it is available and reliable', async () => {
 const timeOrigin = await getFreshPerformanceTimeOrigin();
Expand Down

6 changes: 3 additions & 3 deletions
packages/replay-internal/src/util/createPerformanceEntries.ts

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Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
import { browserPerformanceTimeOrigin } from '@sentry/core';
import { correctedPerformanceTimeOrigin } from '@sentry/core';
import { record } from '@sentry/rrweb';
import { WINDOW } from '../constants';
import type {
Expand DownExpand Up@@ -87,9 +87,9 @@ function createPerformanceEntry(entry: AllPerformanceEntry): ReplayPerformanceEn
}

function getAbsoluteTime(time: number): number {
 // browserPerformanceTimeOrigin can be undefined if `performance` or
 // correctedPerformanceTimeOrigin can be undefined if `performance` or
 // `performance.now` doesn't exist, but this is already checked by this integration
 return ((browserPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
 return ((correctedPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
}

function createPaintEntry(entry: PerformancePaintTiming): ReplayPerformanceEntry<PaintData> {
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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fix(browser): Use drift-corrected time origin for INP, replay and profiling#23067

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fix(browser): Use drift-corrected time origin for INP, replay and profiling
#23067
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5 changes: 4 additions & 1 deletion
packages/browser-utils/src/metrics/webVitalSpans.ts

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Original file line numberDiff line numberDiff line change
@@ -1,6 +1,7 @@
import type { Client, Integration, Span, SpanAttributes } from '@sentry/core';
import {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,

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3
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+4

@logaretmlogaretmAug 9, 2026

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Do we need both? I don't think we would like to use a non-accurate time origin anywhere, or maybe I misunderstood?
 debug,
 getActiveSpan,
 getClient,
Expand DownExpand Up@@ -329,7 +330,9 @@ export function trackInpAsSpan(client: Client): void {
export function _sendInpSpan(inpValue: number, entry: PerformanceEventTiming, standalone = false): void {
 DEBUG_BUILD && debug.log(`Sending INP span (${inpValue})`);

 const startTime = msToSec((browserPerformanceTimeOrigin() as number) + entry.startTime);
 // INP reports on pagehide, potentially hours after the origin cached at init, so the corrected origin is used to stay
 // on the same timeline as span and event timestamps.
 const startTime = msToSec((correctedPerformanceTimeOrigin() as number) + entry.startTime);
 const duration = msToSec(inpValue);
 const interactionType = INP_ENTRY_MAP[entry.name];

Expand Down

3 changes: 3 additions & 0 deletions
packages/browser-utils/test/metrics/webVitalSpans.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -17,6 +17,7 @@ vi.mock('@sentry/core', async () => {
 return {
 ...actual,
 browserPerformanceTimeOrigin: vi.fn(),
 correctedPerformanceTimeOrigin: vi.fn(),
 timestampInSeconds: vi.fn(),
 getCurrentScope: vi.fn(),
 getClient: vi.fn(),
Expand DownExpand Up@@ -475,6 +476,7 @@ describe('_sendInpSpan', () => {
 beforeEach(() => {
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(htmlTreeAsString).mockReturnValue('<button>');
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue(mockSpan as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
Expand DownExpand Up@@ -592,6 +594,7 @@ describe('trackInpAsSpan', () => {

 beforeEach(() => {
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue({ end: vi.fn() } as any);
Expand Down

6 changes: 3 additions & 3 deletions
packages/browser/src/profiling/utils.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -12,7 +12,7 @@ import type {
 ThreadCpuProfile,
} from '@sentry/core/browser';
import {
browserPerformanceTimeOrigin,
correctedPerformanceTimeOrigin,
 debug,
 DEFAULT_ENVIRONMENT,
 forEachEnvelopeItem,
Expand DownExpand Up@@ -339,7 +339,7 @@ function convertToContinuousProfile(input: {
 }

 // Align timestamps to SDK time origin to match span/event timelines
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand DownExpand Up@@ -412,7 +412,7 @@ export function convertJSSelfProfileToSampledFormat(input: JSSelfProfile): Profi
 // when that happens, we need to ensure we are correcting the profile timings so the two timelines stay in sync.
 // Since JS self profiling time origin is always initialized to performance.timeOrigin, we need to adjust for
 // the drift between the SDK selected value and our profile time origin.
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
@cursorcursorBotAug 5, 2026

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Profile elapsed times shift after drift
High Severity
Switching convertJSSelfProfileToSampledFormat to correctedPerformanceTimeOrigin makes adjustForOriginChange non-zero after runtime clock drift. That delta is added into every elapsed_since_start_ns, so the first sample is no longer 0 and all relative sample times shift by the full drift (often negative after device sleep). Continuous profiling absolute timestamps are fine; this only breaks transaction/sampled profiles.
Additional Locations (2)
Fix in CursorFix in Web
Reviewed by Cursor Bugbot for commit 25c1b28. Configure here.
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand Down

7 changes: 6 additions & 1 deletion
packages/core/src/shared-exports.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -274,7 +274,12 @@ export {
 supportsReferrerPolicy,
} from './utils/supports';
export { SyncPromise, rejectedSyncPromise, resolvedSyncPromise } from './utils/syncpromise';
export { browserPerformanceTimeOrigin, dateTimestampInSeconds, timestampInSeconds } from './utils/time';
export {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,
 dateTimestampInSeconds,
 timestampInSeconds,
} from './utils/time';
export {
 TRACEPARENT_REGEXP,
 extractTraceparentData,
Expand Down

24 changes: 22 additions & 2 deletions
packages/core/src/utils/time.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -31,6 +31,12 @@ export function dateTimestampInSeconds(): number {
 return safeDateNow() / ONE_SECOND_IN_MS;
}

/**
 * The time origin `timestampInSeconds` currently maps the monotonic clock against, kept in sync with the corrections it
 * applies. `undefined` until the first `timestampInSeconds` call, and whenever the Performance API is unavailable.
 */
let _correctedTimeOrigin: number | undefined;

/**
 * Returns a wrapper around the native Performance API browser implementation, or undefined for browsers that do not
 * support the API.
Expand All@@ -47,7 +53,7 @@ function createUnixTimestampInSecondsFunc(): () => number {

 // performance.now() is a monotonic clock, which means it starts at 0 when the process begins. To get the current
 // wall clock time (actual UNIX timestamp), we need to add the starting time origin and the current time elapsed.
 let timeOrigin = performance.timeOrigin;
 let timeOrigin = (_correctedTimeOrigin = performance.timeOrigin);

 return () => {
 return withRandomSafeContext(() => {
Expand All@@ -66,7 +72,7 @@ function createUnixTimestampInSecondsFunc(): () => number {
 // See: https://github.com/mdn/content/issues/4713
 // See: https://dev.to/noamr/when-a-millisecond-is-not-a-millisecond-3h6
 if (Math.abs(timeOrigin + performanceNow - dateNow) > CLOCK_DRIFT_THRESHOLD_MS) {
 timeOrigin = dateNow - performanceNow;
 timeOrigin = _correctedTimeOrigin = dateNow - performanceNow;
 }

 return (timeOrigin + performanceNow) / ONE_SECOND_IN_MS;
Expand All@@ -76,6 +82,20 @@ function createUnixTimestampInSecondsFunc(): () => number {

let _cachedTimestampInSeconds: (() => number) | undefined;

/**
 * Returns the time origin (in milliseconds since the UNIX epoch) that {@link timestampInSeconds} currently maps
 * `performance.now()` against, including any correction it has applied for clock drift.
 *
 * Use this over {@link browserPerformanceTimeOrigin} when converting a `PerformanceEntry`'s monotonic `startTime` to
 * wall clock time at the moment the entry is observed, so the result shares a timeline with span and event timestamps.
 * Returns `undefined` if the Performance API is unavailable, in which case monotonic timestamps cannot be converted.
 */
export function correctedPerformanceTimeOrigin(): number | undefined {
 // The origin is only populated once `timestampInSeconds` has resolved which clock source to use.
 timestampInSeconds();
 return _correctedTimeOrigin;
}

/**
 * Returns a timestamp in seconds since the UNIX epoch using either the Performance or Date APIs, depending on the
 * availability of the Performance API.
Expand Down

81 changes: 78 additions & 3 deletions
packages/core/test/lib/utils/time.test.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -9,11 +9,17 @@ async function getFreshPerformanceTimeOrigin() {

let freshImportCounter = 0;

async function getFreshTimestampInSeconds(): Promise<() => number> {
async function getFreshTimeModule(): Promise<{
 timestampInSeconds: () => number;
 correctedPerformanceTimeOrigin: () => number | undefined;
}> {
 // A counter rather than `Date.now()`: these tests run under fake timers, which freeze the wall clock and would
 // otherwise hand out a cached module.
 const timeModule = await import(`../../../src/utils/time?update=${freshImportCounter++}`);
 return timeModule.timestampInSeconds;
 return import(`../../../src/utils/time?update=${freshImportCounter++}`);
}

async function getFreshTimestampInSeconds(): Promise<() => number> {
 return (await getFreshTimeModule()).timestampInSeconds;
}

const RELIABLE_THRESHOLD_MS = 300_000;
Expand DownExpand Up@@ -180,6 +186,75 @@ describe('timestampInSeconds', () => {
 });
});

describe('correctedPerformanceTimeOrigin', () => {
 afterEach(() => {
 vi.useRealTimers();
 vi.unstubAllGlobals();
 });

 it('returns `performance.timeOrigin` while the clocks agree', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const timeOrigin = currentTimeMs - timeSincePageloadMs;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', { timeOrigin, now: () => timeSincePageloadMs });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBe(timeOrigin);
 });

 it('returns the corrected origin after clock drift, without a prior `timestampInSeconds` call', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 expect(correctedPerformanceTimeOrigin()).toBe(currentTimeMs + sleepDurationMs - timeSincePageloadMs);
 });

 it('stays on the same timeline as `timestampInSeconds`', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin, timestampInSeconds } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 // Converting the current `performance.now()` against the origin must yield the same wall clock time that
 // `timestampInSeconds` reports, otherwise perf entries and spans land on diverging timelines.
 expect((correctedPerformanceTimeOrigin() as number) + timeSincePageloadMs).toBe(timestampInSeconds() * 1000);
 });

 it('returns `undefined` if the performance API is unavailable', async () => {
 vi.stubGlobal('performance', undefined);

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBeUndefined();
 });
});

describe('browserPerformanceTimeOrigin', () => {
 it('returns `performance.timeOrigin` if it is available and reliable', async () => {
 const timeOrigin = await getFreshPerformanceTimeOrigin();
Expand Down

6 changes: 3 additions & 3 deletions
packages/replay-internal/src/util/createPerformanceEntries.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
import { browserPerformanceTimeOrigin } from '@sentry/core';
import { correctedPerformanceTimeOrigin } from '@sentry/core';
import { record } from '@sentry/rrweb';
import { WINDOW } from '../constants';
import type {
Expand DownExpand Up@@ -87,9 +87,9 @@ function createPerformanceEntry(entry: AllPerformanceEntry): ReplayPerformanceEn
}

function getAbsoluteTime(time: number): number {
 // browserPerformanceTimeOrigin can be undefined if `performance` or
 // correctedPerformanceTimeOrigin can be undefined if `performance` or
 // `performance.now` doesn't exist, but this is already checked by this integration
 return ((browserPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
 return ((correctedPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
}

function createPaintEntry(entry: PerformancePaintTiming): ReplayPerformanceEntry<PaintData> {
Expand Down
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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fix(browser): Use drift-corrected time origin for INP, replay and profiling#23067

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fix(browser): Use drift-corrected time origin for INP, replay and profiling
#23067
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5 changes: 4 additions & 1 deletion
packages/browser-utils/src/metrics/webVitalSpans.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -1,6 +1,7 @@
import type { Client, Integration, Span, SpanAttributes } from '@sentry/core';
import {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,

Comment on lines

3
 to 
+4

@logaretmlogaretmAug 9, 2026

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Do we need both? I don't think we would like to use a non-accurate time origin anywhere, or maybe I misunderstood?
 debug,
 getActiveSpan,
 getClient,
Expand DownExpand Up@@ -329,7 +330,9 @@ export function trackInpAsSpan(client: Client): void {
export function _sendInpSpan(inpValue: number, entry: PerformanceEventTiming, standalone = false): void {
 DEBUG_BUILD && debug.log(`Sending INP span (${inpValue})`);

 const startTime = msToSec((browserPerformanceTimeOrigin() as number) + entry.startTime);
 // INP reports on pagehide, potentially hours after the origin cached at init, so the corrected origin is used to stay
 // on the same timeline as span and event timestamps.
 const startTime = msToSec((correctedPerformanceTimeOrigin() as number) + entry.startTime);
 const duration = msToSec(inpValue);
 const interactionType = INP_ENTRY_MAP[entry.name];

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3 changes: 3 additions & 0 deletions
packages/browser-utils/test/metrics/webVitalSpans.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -17,6 +17,7 @@ vi.mock('@sentry/core', async () => {
 return {
 ...actual,
 browserPerformanceTimeOrigin: vi.fn(),
 correctedPerformanceTimeOrigin: vi.fn(),
 timestampInSeconds: vi.fn(),
 getCurrentScope: vi.fn(),
 getClient: vi.fn(),
Expand DownExpand Up@@ -475,6 +476,7 @@ describe('_sendInpSpan', () => {
 beforeEach(() => {
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(htmlTreeAsString).mockReturnValue('<button>');
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue(mockSpan as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
Expand DownExpand Up@@ -592,6 +594,7 @@ describe('trackInpAsSpan', () => {

 beforeEach(() => {
 vi.mocked(SentryCore.browserPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.correctedPerformanceTimeOrigin).mockReturnValue(1000);
 vi.mocked(SentryCore.getCurrentScope).mockReturnValue(mockScope as any);
 vi.mocked(SentryCore.getActiveSpan).mockReturnValue(undefined);
 vi.mocked(SentryCore.startInactiveSpan).mockReturnValue({ end: vi.fn() } as any);
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6 changes: 3 additions & 3 deletions
packages/browser/src/profiling/utils.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -12,7 +12,7 @@ import type {
 ThreadCpuProfile,
} from '@sentry/core/browser';
import {
browserPerformanceTimeOrigin,
correctedPerformanceTimeOrigin,
 debug,
 DEFAULT_ENVIRONMENT,
 forEachEnvelopeItem,
Expand DownExpand Up@@ -339,7 +339,7 @@ function convertToContinuousProfile(input: {
 }

 // Align timestamps to SDK time origin to match span/event timelines
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

Expand DownExpand Up@@ -412,7 +412,7 @@ export function convertJSSelfProfileToSampledFormat(input: JSSelfProfile): Profi
 // when that happens, we need to ensure we are correcting the profile timings so the two timelines stay in sync.
 // Since JS self profiling time origin is always initialized to performance.timeOrigin, we need to adjust for
 // the drift between the SDK selected value and our profile time origin.
 const perfOrigin = browserPerformanceTimeOrigin();
 const perfOrigin = correctedPerformanceTimeOrigin();
@cursorcursorBotAug 5, 2026

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Profile elapsed times shift after drift
High Severity
Switching convertJSSelfProfileToSampledFormat to correctedPerformanceTimeOrigin makes adjustForOriginChange non-zero after runtime clock drift. That delta is added into every elapsed_since_start_ns, so the first sample is no longer 0 and all relative sample times shift by the full drift (often negative after device sleep). Continuous profiling absolute timestamps are fine; this only breaks transaction/sampled profiles.
Additional Locations (2)
Fix in CursorFix in Web
Reviewed by Cursor Bugbot for commit 25c1b28. Configure here.
 const origin = typeof performance.timeOrigin === 'number' ? performance.timeOrigin : perfOrigin || 0;
 const adjustForOriginChange = origin - (perfOrigin || origin);

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7 changes: 6 additions & 1 deletion
packages/core/src/shared-exports.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -274,7 +274,12 @@ export {
 supportsReferrerPolicy,
} from './utils/supports';
export { SyncPromise, rejectedSyncPromise, resolvedSyncPromise } from './utils/syncpromise';
export { browserPerformanceTimeOrigin, dateTimestampInSeconds, timestampInSeconds } from './utils/time';
export {
 browserPerformanceTimeOrigin,
 correctedPerformanceTimeOrigin,
 dateTimestampInSeconds,
 timestampInSeconds,
} from './utils/time';
export {
 TRACEPARENT_REGEXP,
 extractTraceparentData,
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24 changes: 22 additions & 2 deletions
packages/core/src/utils/time.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -31,6 +31,12 @@ export function dateTimestampInSeconds(): number {
 return safeDateNow() / ONE_SECOND_IN_MS;
}

/**
 * The time origin `timestampInSeconds` currently maps the monotonic clock against, kept in sync with the corrections it
 * applies. `undefined` until the first `timestampInSeconds` call, and whenever the Performance API is unavailable.
 */
let _correctedTimeOrigin: number | undefined;

/**
 * Returns a wrapper around the native Performance API browser implementation, or undefined for browsers that do not
 * support the API.
Expand All@@ -47,7 +53,7 @@ function createUnixTimestampInSecondsFunc(): () => number {

 // performance.now() is a monotonic clock, which means it starts at 0 when the process begins. To get the current
 // wall clock time (actual UNIX timestamp), we need to add the starting time origin and the current time elapsed.
 let timeOrigin = performance.timeOrigin;
 let timeOrigin = (_correctedTimeOrigin = performance.timeOrigin);

 return () => {
 return withRandomSafeContext(() => {
Expand All@@ -66,7 +72,7 @@ function createUnixTimestampInSecondsFunc(): () => number {
 // See: https://github.com/mdn/content/issues/4713
 // See: https://dev.to/noamr/when-a-millisecond-is-not-a-millisecond-3h6
 if (Math.abs(timeOrigin + performanceNow - dateNow) > CLOCK_DRIFT_THRESHOLD_MS) {
 timeOrigin = dateNow - performanceNow;
 timeOrigin = _correctedTimeOrigin = dateNow - performanceNow;
 }

 return (timeOrigin + performanceNow) / ONE_SECOND_IN_MS;
Expand All@@ -76,6 +82,20 @@ function createUnixTimestampInSecondsFunc(): () => number {

let _cachedTimestampInSeconds: (() => number) | undefined;

/**
 * Returns the time origin (in milliseconds since the UNIX epoch) that {@link timestampInSeconds} currently maps
 * `performance.now()` against, including any correction it has applied for clock drift.
 *
 * Use this over {@link browserPerformanceTimeOrigin} when converting a `PerformanceEntry`'s monotonic `startTime` to
 * wall clock time at the moment the entry is observed, so the result shares a timeline with span and event timestamps.
 * Returns `undefined` if the Performance API is unavailable, in which case monotonic timestamps cannot be converted.
 */
export function correctedPerformanceTimeOrigin(): number | undefined {
 // The origin is only populated once `timestampInSeconds` has resolved which clock source to use.
 timestampInSeconds();
 return _correctedTimeOrigin;
}

/**
 * Returns a timestamp in seconds since the UNIX epoch using either the Performance or Date APIs, depending on the
 * availability of the Performance API.
Expand Down

81 changes: 78 additions & 3 deletions
packages/core/test/lib/utils/time.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -9,11 +9,17 @@ async function getFreshPerformanceTimeOrigin() {

let freshImportCounter = 0;

async function getFreshTimestampInSeconds(): Promise<() => number> {
async function getFreshTimeModule(): Promise<{
 timestampInSeconds: () => number;
 correctedPerformanceTimeOrigin: () => number | undefined;
}> {
 // A counter rather than `Date.now()`: these tests run under fake timers, which freeze the wall clock and would
 // otherwise hand out a cached module.
 const timeModule = await import(`../../../src/utils/time?update=${freshImportCounter++}`);
 return timeModule.timestampInSeconds;
 return import(`../../../src/utils/time?update=${freshImportCounter++}`);
}

async function getFreshTimestampInSeconds(): Promise<() => number> {
 return (await getFreshTimeModule()).timestampInSeconds;
}

const RELIABLE_THRESHOLD_MS = 300_000;
Expand DownExpand Up@@ -180,6 +186,75 @@ describe('timestampInSeconds', () => {
 });
});

describe('correctedPerformanceTimeOrigin', () => {
 afterEach(() => {
 vi.useRealTimers();
 vi.unstubAllGlobals();
 });

 it('returns `performance.timeOrigin` while the clocks agree', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const timeOrigin = currentTimeMs - timeSincePageloadMs;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', { timeOrigin, now: () => timeSincePageloadMs });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBe(timeOrigin);
 });

 it('returns the corrected origin after clock drift, without a prior `timestampInSeconds` call', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 expect(correctedPerformanceTimeOrigin()).toBe(currentTimeMs + sleepDurationMs - timeSincePageloadMs);
 });

 it('stays on the same timeline as `timestampInSeconds`', async () => {
 const currentTimeMs = 1767778040866;
 const timeSincePageloadMs = 1_000;
 const sleepDurationMs = RELIABLE_THRESHOLD_MS + 60_000;

 vi.useFakeTimers();
 vi.setSystemTime(new Date(currentTimeMs));
 vi.stubGlobal('performance', {
 timeOrigin: currentTimeMs - timeSincePageloadMs,
 now: () => timeSincePageloadMs,
 });

 const { correctedPerformanceTimeOrigin, timestampInSeconds } = await getFreshTimeModule();

 vi.setSystemTime(new Date(currentTimeMs + sleepDurationMs));

 // Converting the current `performance.now()` against the origin must yield the same wall clock time that
 // `timestampInSeconds` reports, otherwise perf entries and spans land on diverging timelines.
 expect((correctedPerformanceTimeOrigin() as number) + timeSincePageloadMs).toBe(timestampInSeconds() * 1000);
 });

 it('returns `undefined` if the performance API is unavailable', async () => {
 vi.stubGlobal('performance', undefined);

 const { correctedPerformanceTimeOrigin } = await getFreshTimeModule();

 expect(correctedPerformanceTimeOrigin()).toBeUndefined();
 });
});

describe('browserPerformanceTimeOrigin', () => {
 it('returns `performance.timeOrigin` if it is available and reliable', async () => {
 const timeOrigin = await getFreshPerformanceTimeOrigin();
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6 changes: 3 additions & 3 deletions
packages/replay-internal/src/util/createPerformanceEntries.ts

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Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
import { browserPerformanceTimeOrigin } from '@sentry/core';
import { correctedPerformanceTimeOrigin } from '@sentry/core';
import { record } from '@sentry/rrweb';
import { WINDOW } from '../constants';
import type {
Expand DownExpand Up@@ -87,9 +87,9 @@ function createPerformanceEntry(entry: AllPerformanceEntry): ReplayPerformanceEn
}

function getAbsoluteTime(time: number): number {
 // browserPerformanceTimeOrigin can be undefined if `performance` or
 // correctedPerformanceTimeOrigin can be undefined if `performance` or
 // `performance.now` doesn't exist, but this is already checked by this integration
 return ((browserPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
 return ((correctedPerformanceTimeOrigin() || WINDOW.performance.timeOrigin) + time) / 1000;
}

function createPaintEntry(entry: PerformancePaintTiming): ReplayPerformanceEntry<PaintData> {
Expand Down
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