Fix chat scroll jitter during streaming; respect reduced motion#11

New issue

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

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
kateebonner merged 1 commit into from
Jul 9, 2026
Merged

Fix chat scroll jitter during streaming; respect reduced motion #11

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
11 changes: 10 additions & 1 deletion packages/app/src/pages/session.tsx
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -1200,8 +1200,17 @@ export default function Page() {
),
)

// Only follow the bottom while the model is actually streaming. This was
// previously hard-coded to `true`, so the auto-scroller's ResizeObserver
// force-scrolled on *any* reflow (image load, tool accordion expand, font
// swap, layout settle) — which read as the chat "jumping" on its own. Gating
// it on the session's real working state also stops it from competing with
// the timeline's own bottom-lock outside of streaming.
const autoScroll = createAutoScroll({
working: () => true,
working: () => {
const id = params.id
return id ? sync.data.session_working(id) : false
},
overflowAnchor: "dynamic",
})

Expand Down
15 changes: 12 additions & 3 deletions packages/app/src/pages/session/message-timeline.tsx
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -568,12 +568,21 @@ export function MessageTimeline(props: {
createEffect(
on(
() => [timelineRowKeys(), activeAssistantContentVersion(), sessionStatus().type] as const,
() => {
(curr, prev) => {
if (!virtualizer) return
if (!props.shouldAnchorBottom() && !measuredBottomAnchored) return
const keys = timelineRowKeys()
const keys = curr[0]
if (keys.length === 0) return
virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
// Only realign via virtua (an estimate-based scroll that can visibly
// pre-jump before item heights are measured) when the *set of rows*
// changes or the session status flips. Pure intra-row growth while a
// token streams is left to the measured-bottom rAF lock below, which
// pins against the real DOM height — so the two mechanisms stop landing
// on slightly different scroll positions frame-to-frame. `timelineRowKeys`
// is memoized with `equals: sameKeys`, so its reference only changes when
// the row set actually changes, making this comparison cheap and exact.
const rowsChanged = !prev || prev[0] !== keys || prev[2] !== curr[2]
if (rowsChanged) virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
scheduleMeasuredBottomAnchor()
},
{ defer: true },
Expand Down
14 changes: 14 additions & 0 deletions packages/ui/src/components/message-part.tsx
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -60,6 +60,9 @@ import { useLocation } from "@solidjs/router"
import { attached, inline, kind } from "./message-file"
import { readPartText } from "./message-part-text"

const reducedMotion = () =>
typeof window !== "undefined" && !!window.matchMedia?.("(prefers-reduced-motion: reduce)").matches

async function writeClipboard(text: string): Promise<boolean> {
const body = typeof document === "undefined" ? undefined : document.body
if (body) {
Expand DownExpand Up@@ -90,6 +93,17 @@ function ShellSubmessage(props: { text: string; animate?: boolean }) {

onMount(() => {
if (!props.animate) return
// The initial render collapses width to 0 and hides the value behind a blur;
// if the user prefers reduced motion, snap straight to the resting state
// instead of animating (and instead of leaving it stuck collapsed/hidden).
if (reducedMotion()) {
if (widthRef) widthRef.style.width = "auto"
if (valueRef) {
valueRef.style.opacity = "1"
valueRef.style.filter = "blur(0px)"
}
return
}
requestAnimationFrame(() => {
if (widthRef) {
animate(widthRef, { width: "auto" }, { type: "spring", visualDuration: 0.25, bounce: 0 })
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" + '

Skip to content
Fix chat scroll jitter during streaming; respect reduced motion#11

New issue

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

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

kateebonner
merged 1 commit into

from

Jul 9, 2026
 Merged


Fix chat scroll jitter during streaming; respect reduced motion
#11
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


1 commit


Select commit


File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


11 changes: 10 additions & 1 deletion
packages/app/src/pages/session.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1200,8 +1200,17 @@ export default function Page() {
 ),
 )

 // Only follow the bottom while the model is actually streaming. This was
 // previously hard-coded to `true`, so the auto-scroller's ResizeObserver
 // force-scrolled on *any* reflow (image load, tool accordion expand, font
 // swap, layout settle) — which read as the chat "jumping" on its own. Gating
 // it on the session's real working state also stops it from competing with
 // the timeline's own bottom-lock outside of streaming.
 const autoScroll = createAutoScroll({
 working: () => true,
 working: () => {
 const id = params.id
 return id ? sync.data.session_working(id) : false
 },
 overflowAnchor: "dynamic",
 })

Expand Down

15 changes: 12 additions & 3 deletions
packages/app/src/pages/session/message-timeline.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -568,12 +568,21 @@ export function MessageTimeline(props: {
 createEffect(
 on(
 () => [timelineRowKeys(), activeAssistantContentVersion(), sessionStatus().type] as const,
 () => {
 (curr, prev) => {
 if (!virtualizer) return
 if (!props.shouldAnchorBottom() && !measuredBottomAnchored) return
 const keys = timelineRowKeys()
 const keys = curr[0]
 if (keys.length === 0) return
 virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 // Only realign via virtua (an estimate-based scroll that can visibly
 // pre-jump before item heights are measured) when the *set of rows*
 // changes or the session status flips. Pure intra-row growth while a
 // token streams is left to the measured-bottom rAF lock below, which
 // pins against the real DOM height — so the two mechanisms stop landing
 // on slightly different scroll positions frame-to-frame. `timelineRowKeys`
 // is memoized with `equals: sameKeys`, so its reference only changes when
 // the row set actually changes, making this comparison cheap and exact.
 const rowsChanged = !prev || prev[0] !== keys || prev[2] !== curr[2]
 if (rowsChanged) virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 scheduleMeasuredBottomAnchor()
 },
 { defer: true },
Expand Down

14 changes: 14 additions & 0 deletions
packages/ui/src/components/message-part.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,6 +60,9 @@ import { useLocation } from "@solidjs/router"
import { attached, inline, kind } from "./message-file"
import { readPartText } from "./message-part-text"

const reducedMotion = () =>
 typeof window !== "undefined" && !!window.matchMedia?.("(prefers-reduced-motion: reduce)").matches

async function writeClipboard(text: string): Promise<boolean> {
 const body = typeof document === "undefined" ? undefined : document.body
 if (body) {
Expand DownExpand Up@@ -90,6 +93,17 @@ function ShellSubmessage(props: { text: string; animate?: boolean }) {

 onMount(() => {
 if (!props.animate) return
 // The initial render collapses width to 0 and hides the value behind a blur;
 // if the user prefers reduced motion, snap straight to the resting state
 // instead of animating (and instead of leaving it stuck collapsed/hidden).
 if (reducedMotion()) {
 if (widthRef) widthRef.style.width = "auto"
 if (valueRef) {
 valueRef.style.opacity = "1"
 valueRef.style.filter = "blur(0px)"
 }
 return
 }
 requestAnimationFrame(() => {
 if (widthRef) {
 animate(widthRef, { width: "auto" }, { type: "spring", visualDuration: 0.25, bounce: 0 })
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('^' + ".*" + '

Skip to content
Fix chat scroll jitter during streaming; respect reduced motion#11

New issue

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

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

kateebonner
merged 1 commit into

from

Jul 9, 2026
 Merged


Fix chat scroll jitter during streaming; respect reduced motion
#11
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


1 commit


Select commit


File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


11 changes: 10 additions & 1 deletion
packages/app/src/pages/session.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1200,8 +1200,17 @@ export default function Page() {
 ),
 )

 // Only follow the bottom while the model is actually streaming. This was
 // previously hard-coded to `true`, so the auto-scroller's ResizeObserver
 // force-scrolled on *any* reflow (image load, tool accordion expand, font
 // swap, layout settle) — which read as the chat "jumping" on its own. Gating
 // it on the session's real working state also stops it from competing with
 // the timeline's own bottom-lock outside of streaming.
 const autoScroll = createAutoScroll({
 working: () => true,
 working: () => {
 const id = params.id
 return id ? sync.data.session_working(id) : false
 },
 overflowAnchor: "dynamic",
 })

Expand Down

15 changes: 12 additions & 3 deletions
packages/app/src/pages/session/message-timeline.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -568,12 +568,21 @@ export function MessageTimeline(props: {
 createEffect(
 on(
 () => [timelineRowKeys(), activeAssistantContentVersion(), sessionStatus().type] as const,
 () => {
 (curr, prev) => {
 if (!virtualizer) return
 if (!props.shouldAnchorBottom() && !measuredBottomAnchored) return
 const keys = timelineRowKeys()
 const keys = curr[0]
 if (keys.length === 0) return
 virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 // Only realign via virtua (an estimate-based scroll that can visibly
 // pre-jump before item heights are measured) when the *set of rows*
 // changes or the session status flips. Pure intra-row growth while a
 // token streams is left to the measured-bottom rAF lock below, which
 // pins against the real DOM height — so the two mechanisms stop landing
 // on slightly different scroll positions frame-to-frame. `timelineRowKeys`
 // is memoized with `equals: sameKeys`, so its reference only changes when
 // the row set actually changes, making this comparison cheap and exact.
 const rowsChanged = !prev || prev[0] !== keys || prev[2] !== curr[2]
 if (rowsChanged) virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 scheduleMeasuredBottomAnchor()
 },
 { defer: true },
Expand Down

14 changes: 14 additions & 0 deletions
packages/ui/src/components/message-part.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,6 +60,9 @@ import { useLocation } from "@solidjs/router"
import { attached, inline, kind } from "./message-file"
import { readPartText } from "./message-part-text"

const reducedMotion = () =>
 typeof window !== "undefined" && !!window.matchMedia?.("(prefers-reduced-motion: reduce)").matches

async function writeClipboard(text: string): Promise<boolean> {
 const body = typeof document === "undefined" ? undefined : document.body
 if (body) {
Expand DownExpand Up@@ -90,6 +93,17 @@ function ShellSubmessage(props: { text: string; animate?: boolean }) {

 onMount(() => {
 if (!props.animate) return
 // The initial render collapses width to 0 and hides the value behind a blur;
 // if the user prefers reduced motion, snap straight to the resting state
 // instead of animating (and instead of leaving it stuck collapsed/hidden).
 if (reducedMotion()) {
 if (widthRef) widthRef.style.width = "auto"
 if (valueRef) {
 valueRef.style.opacity = "1"
 valueRef.style.filter = "blur(0px)"
 }
 return
 }
 requestAnimationFrame(() => {
 if (widthRef) {
 animate(widthRef, { width: "auto" }, { type: "spring", visualDuration: 0.25, bounce: 0 })
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 chat scroll jitter during streaming; respect reduced motion#11

New issue

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

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

kateebonner
merged 1 commit into

from

Jul 9, 2026
 Merged


Fix chat scroll jitter during streaming; respect reduced motion
#11
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


1 commit


Select commit


File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


11 changes: 10 additions & 1 deletion
packages/app/src/pages/session.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1200,8 +1200,17 @@ export default function Page() {
 ),
 )

 // Only follow the bottom while the model is actually streaming. This was
 // previously hard-coded to `true`, so the auto-scroller's ResizeObserver
 // force-scrolled on *any* reflow (image load, tool accordion expand, font
 // swap, layout settle) — which read as the chat "jumping" on its own. Gating
 // it on the session's real working state also stops it from competing with
 // the timeline's own bottom-lock outside of streaming.
 const autoScroll = createAutoScroll({
 working: () => true,
 working: () => {
 const id = params.id
 return id ? sync.data.session_working(id) : false
 },
 overflowAnchor: "dynamic",
 })

Expand Down

15 changes: 12 additions & 3 deletions
packages/app/src/pages/session/message-timeline.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -568,12 +568,21 @@ export function MessageTimeline(props: {
 createEffect(
 on(
 () => [timelineRowKeys(), activeAssistantContentVersion(), sessionStatus().type] as const,
 () => {
 (curr, prev) => {
 if (!virtualizer) return
 if (!props.shouldAnchorBottom() && !measuredBottomAnchored) return
 const keys = timelineRowKeys()
 const keys = curr[0]
 if (keys.length === 0) return
 virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 // Only realign via virtua (an estimate-based scroll that can visibly
 // pre-jump before item heights are measured) when the *set of rows*
 // changes or the session status flips. Pure intra-row growth while a
 // token streams is left to the measured-bottom rAF lock below, which
 // pins against the real DOM height — so the two mechanisms stop landing
 // on slightly different scroll positions frame-to-frame. `timelineRowKeys`
 // is memoized with `equals: sameKeys`, so its reference only changes when
 // the row set actually changes, making this comparison cheap and exact.
 const rowsChanged = !prev || prev[0] !== keys || prev[2] !== curr[2]
 if (rowsChanged) virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 scheduleMeasuredBottomAnchor()
 },
 { defer: true },
Expand Down

14 changes: 14 additions & 0 deletions
packages/ui/src/components/message-part.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,6 +60,9 @@ import { useLocation } from "@solidjs/router"
import { attached, inline, kind } from "./message-file"
import { readPartText } from "./message-part-text"

const reducedMotion = () =>
 typeof window !== "undefined" && !!window.matchMedia?.("(prefers-reduced-motion: reduce)").matches

async function writeClipboard(text: string): Promise<boolean> {
 const body = typeof document === "undefined" ? undefined : document.body
 if (body) {
Expand DownExpand Up@@ -90,6 +93,17 @@ function ShellSubmessage(props: { text: string; animate?: boolean }) {

 onMount(() => {
 if (!props.animate) return
 // The initial render collapses width to 0 and hides the value behind a blur;
 // if the user prefers reduced motion, snap straight to the resting state
 // instead of animating (and instead of leaving it stuck collapsed/hidden).
 if (reducedMotion()) {
 if (widthRef) widthRef.style.width = "auto"
 if (valueRef) {
 valueRef.style.opacity = "1"
 valueRef.style.filter = "blur(0px)"
 }
 return
 }
 requestAnimationFrame(() => {
 if (widthRef) {
 animate(widthRef, { width: "auto" }, { type: "spring", visualDuration: 0.25, bounce: 0 })
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" + '

Skip to content
Fix chat scroll jitter during streaming; respect reduced motion#11

New issue

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

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

kateebonner
merged 1 commit into

from

Jul 9, 2026
 Merged


Fix chat scroll jitter during streaming; respect reduced motion
#11
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


1 commit


Select commit


File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


11 changes: 10 additions & 1 deletion
packages/app/src/pages/session.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1200,8 +1200,17 @@ export default function Page() {
 ),
 )

 // Only follow the bottom while the model is actually streaming. This was
 // previously hard-coded to `true`, so the auto-scroller's ResizeObserver
 // force-scrolled on *any* reflow (image load, tool accordion expand, font
 // swap, layout settle) — which read as the chat "jumping" on its own. Gating
 // it on the session's real working state also stops it from competing with
 // the timeline's own bottom-lock outside of streaming.
 const autoScroll = createAutoScroll({
 working: () => true,
 working: () => {
 const id = params.id
 return id ? sync.data.session_working(id) : false
 },
 overflowAnchor: "dynamic",
 })

Expand Down

15 changes: 12 additions & 3 deletions
packages/app/src/pages/session/message-timeline.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -568,12 +568,21 @@ export function MessageTimeline(props: {
 createEffect(
 on(
 () => [timelineRowKeys(), activeAssistantContentVersion(), sessionStatus().type] as const,
 () => {
 (curr, prev) => {
 if (!virtualizer) return
 if (!props.shouldAnchorBottom() && !measuredBottomAnchored) return
 const keys = timelineRowKeys()
 const keys = curr[0]
 if (keys.length === 0) return
 virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 // Only realign via virtua (an estimate-based scroll that can visibly
 // pre-jump before item heights are measured) when the *set of rows*
 // changes or the session status flips. Pure intra-row growth while a
 // token streams is left to the measured-bottom rAF lock below, which
 // pins against the real DOM height — so the two mechanisms stop landing
 // on slightly different scroll positions frame-to-frame. `timelineRowKeys`
 // is memoized with `equals: sameKeys`, so its reference only changes when
 // the row set actually changes, making this comparison cheap and exact.
 const rowsChanged = !prev || prev[0] !== keys || prev[2] !== curr[2]
 if (rowsChanged) virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 scheduleMeasuredBottomAnchor()
 },
 { defer: true },
Expand Down

14 changes: 14 additions & 0 deletions
packages/ui/src/components/message-part.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,6 +60,9 @@ import { useLocation } from "@solidjs/router"
import { attached, inline, kind } from "./message-file"
import { readPartText } from "./message-part-text"

const reducedMotion = () =>
 typeof window !== "undefined" && !!window.matchMedia?.("(prefers-reduced-motion: reduce)").matches

async function writeClipboard(text: string): Promise<boolean> {
 const body = typeof document === "undefined" ? undefined : document.body
 if (body) {
Expand DownExpand Up@@ -90,6 +93,17 @@ function ShellSubmessage(props: { text: string; animate?: boolean }) {

 onMount(() => {
 if (!props.animate) return
 // The initial render collapses width to 0 and hides the value behind a blur;
 // if the user prefers reduced motion, snap straight to the resting state
 // instead of animating (and instead of leaving it stuck collapsed/hidden).
 if (reducedMotion()) {
 if (widthRef) widthRef.style.width = "auto"
 if (valueRef) {
 valueRef.style.opacity = "1"
 valueRef.style.filter = "blur(0px)"
 }
 return
 }
 requestAnimationFrame(() => {
 if (widthRef) {
 animate(widthRef, { width: "auto" }, { type: "spring", visualDuration: 0.25, bounce: 0 })
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 chat scroll jitter during streaming; respect reduced motion#11

New issue

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

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

kateebonner
merged 1 commit into

from

Jul 9, 2026
 Merged


Fix chat scroll jitter during streaming; respect reduced motion
#11
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


1 commit


Select commit


File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


11 changes: 10 additions & 1 deletion
packages/app/src/pages/session.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1200,8 +1200,17 @@ export default function Page() {
 ),
 )

 // Only follow the bottom while the model is actually streaming. This was
 // previously hard-coded to `true`, so the auto-scroller's ResizeObserver
 // force-scrolled on *any* reflow (image load, tool accordion expand, font
 // swap, layout settle) — which read as the chat "jumping" on its own. Gating
 // it on the session's real working state also stops it from competing with
 // the timeline's own bottom-lock outside of streaming.
 const autoScroll = createAutoScroll({
 working: () => true,
 working: () => {
 const id = params.id
 return id ? sync.data.session_working(id) : false
 },
 overflowAnchor: "dynamic",
 })

Expand Down

15 changes: 12 additions & 3 deletions
packages/app/src/pages/session/message-timeline.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -568,12 +568,21 @@ export function MessageTimeline(props: {
 createEffect(
 on(
 () => [timelineRowKeys(), activeAssistantContentVersion(), sessionStatus().type] as const,
 () => {
 (curr, prev) => {
 if (!virtualizer) return
 if (!props.shouldAnchorBottom() && !measuredBottomAnchored) return
 const keys = timelineRowKeys()
 const keys = curr[0]
 if (keys.length === 0) return
 virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 // Only realign via virtua (an estimate-based scroll that can visibly
 // pre-jump before item heights are measured) when the *set of rows*
 // changes or the session status flips. Pure intra-row growth while a
 // token streams is left to the measured-bottom rAF lock below, which
 // pins against the real DOM height — so the two mechanisms stop landing
 // on slightly different scroll positions frame-to-frame. `timelineRowKeys`
 // is memoized with `equals: sameKeys`, so its reference only changes when
 // the row set actually changes, making this comparison cheap and exact.
 const rowsChanged = !prev || prev[0] !== keys || prev[2] !== curr[2]
 if (rowsChanged) virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 scheduleMeasuredBottomAnchor()
 },
 { defer: true },
Expand Down

14 changes: 14 additions & 0 deletions
packages/ui/src/components/message-part.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,6 +60,9 @@ import { useLocation } from "@solidjs/router"
import { attached, inline, kind } from "./message-file"
import { readPartText } from "./message-part-text"

const reducedMotion = () =>
 typeof window !== "undefined" && !!window.matchMedia?.("(prefers-reduced-motion: reduce)").matches

async function writeClipboard(text: string): Promise<boolean> {
 const body = typeof document === "undefined" ? undefined : document.body
 if (body) {
Expand DownExpand Up@@ -90,6 +93,17 @@ function ShellSubmessage(props: { text: string; animate?: boolean }) {

 onMount(() => {
 if (!props.animate) return
 // The initial render collapses width to 0 and hides the value behind a blur;
 // if the user prefers reduced motion, snap straight to the resting state
 // instead of animating (and instead of leaving it stuck collapsed/hidden).
 if (reducedMotion()) {
 if (widthRef) widthRef.style.width = "auto"
 if (valueRef) {
 valueRef.style.opacity = "1"
 valueRef.style.filter = "blur(0px)"
 }
 return
 }
 requestAnimationFrame(() => {
 if (widthRef) {
 animate(widthRef, { width: "auto" }, { type: "spring", visualDuration: 0.25, bounce: 0 })
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('^' + ".*" + '

Skip to content
Fix chat scroll jitter during streaming; respect reduced motion#11

New issue

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

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

kateebonner
merged 1 commit into

from

Jul 9, 2026
 Merged


Fix chat scroll jitter during streaming; respect reduced motion
#11
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


1 commit


Select commit


File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


11 changes: 10 additions & 1 deletion
packages/app/src/pages/session.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1200,8 +1200,17 @@ export default function Page() {
 ),
 )

 // Only follow the bottom while the model is actually streaming. This was
 // previously hard-coded to `true`, so the auto-scroller's ResizeObserver
 // force-scrolled on *any* reflow (image load, tool accordion expand, font
 // swap, layout settle) — which read as the chat "jumping" on its own. Gating
 // it on the session's real working state also stops it from competing with
 // the timeline's own bottom-lock outside of streaming.
 const autoScroll = createAutoScroll({
 working: () => true,
 working: () => {
 const id = params.id
 return id ? sync.data.session_working(id) : false
 },
 overflowAnchor: "dynamic",
 })

Expand Down

15 changes: 12 additions & 3 deletions
packages/app/src/pages/session/message-timeline.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -568,12 +568,21 @@ export function MessageTimeline(props: {
 createEffect(
 on(
 () => [timelineRowKeys(), activeAssistantContentVersion(), sessionStatus().type] as const,
 () => {
 (curr, prev) => {
 if (!virtualizer) return
 if (!props.shouldAnchorBottom() && !measuredBottomAnchored) return
 const keys = timelineRowKeys()
 const keys = curr[0]
 if (keys.length === 0) return
 virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 // Only realign via virtua (an estimate-based scroll that can visibly
 // pre-jump before item heights are measured) when the *set of rows*
 // changes or the session status flips. Pure intra-row growth while a
 // token streams is left to the measured-bottom rAF lock below, which
 // pins against the real DOM height — so the two mechanisms stop landing
 // on slightly different scroll positions frame-to-frame. `timelineRowKeys`
 // is memoized with `equals: sameKeys`, so its reference only changes when
 // the row set actually changes, making this comparison cheap and exact.
 const rowsChanged = !prev || prev[0] !== keys || prev[2] !== curr[2]
 if (rowsChanged) virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 scheduleMeasuredBottomAnchor()
 },
 { defer: true },
Expand Down

14 changes: 14 additions & 0 deletions
packages/ui/src/components/message-part.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,6 +60,9 @@ import { useLocation } from "@solidjs/router"
import { attached, inline, kind } from "./message-file"
import { readPartText } from "./message-part-text"

const reducedMotion = () =>
 typeof window !== "undefined" && !!window.matchMedia?.("(prefers-reduced-motion: reduce)").matches

async function writeClipboard(text: string): Promise<boolean> {
 const body = typeof document === "undefined" ? undefined : document.body
 if (body) {
Expand DownExpand Up@@ -90,6 +93,17 @@ function ShellSubmessage(props: { text: string; animate?: boolean }) {

 onMount(() => {
 if (!props.animate) return
 // The initial render collapses width to 0 and hides the value behind a blur;
 // if the user prefers reduced motion, snap straight to the resting state
 // instead of animating (and instead of leaving it stuck collapsed/hidden).
 if (reducedMotion()) {
 if (widthRef) widthRef.style.width = "auto"
 if (valueRef) {
 valueRef.style.opacity = "1"
 valueRef.style.filter = "blur(0px)"
 }
 return
 }
 requestAnimationFrame(() => {
 if (widthRef) {
 animate(widthRef, { width: "auto" }, { type: "spring", visualDuration: 0.25, bounce: 0 })
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); }
})();
})();

Skip to content
Fix chat scroll jitter during streaming; respect reduced motion#11

New issue

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

 Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and
privacy statement. We’ll occasionally send you account related emails.

Already on GitHub?
Sign in
to your account

 Merged

kateebonner
merged 1 commit into

from

Jul 9, 2026
 Merged


Fix chat scroll jitter during streaming; respect reduced motion
#11
Show file tree
Hide file tree
 Changes from all commits
Commits

Show all changes


1 commit


Select commit


File filter

Filter by extension
Filter by extension
Conversations

Failed to load comments. 
Loading
Jump to

Jump to file


Failed to load files. 
Loading
 Diff view

 Diff view


11 changes: 10 additions & 1 deletion
packages/app/src/pages/session.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -1200,8 +1200,17 @@ export default function Page() {
 ),
 )

 // Only follow the bottom while the model is actually streaming. This was
 // previously hard-coded to `true`, so the auto-scroller's ResizeObserver
 // force-scrolled on *any* reflow (image load, tool accordion expand, font
 // swap, layout settle) — which read as the chat "jumping" on its own. Gating
 // it on the session's real working state also stops it from competing with
 // the timeline's own bottom-lock outside of streaming.
 const autoScroll = createAutoScroll({
 working: () => true,
 working: () => {
 const id = params.id
 return id ? sync.data.session_working(id) : false
 },
 overflowAnchor: "dynamic",
 })

Expand Down

15 changes: 12 additions & 3 deletions
packages/app/src/pages/session/message-timeline.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -568,12 +568,21 @@ export function MessageTimeline(props: {
 createEffect(
 on(
 () => [timelineRowKeys(), activeAssistantContentVersion(), sessionStatus().type] as const,
 () => {
 (curr, prev) => {
 if (!virtualizer) return
 if (!props.shouldAnchorBottom() && !measuredBottomAnchored) return
 const keys = timelineRowKeys()
 const keys = curr[0]
 if (keys.length === 0) return
 virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 // Only realign via virtua (an estimate-based scroll that can visibly
 // pre-jump before item heights are measured) when the *set of rows*
 // changes or the session status flips. Pure intra-row growth while a
 // token streams is left to the measured-bottom rAF lock below, which
 // pins against the real DOM height — so the two mechanisms stop landing
 // on slightly different scroll positions frame-to-frame. `timelineRowKeys`
 // is memoized with `equals: sameKeys`, so its reference only changes when
 // the row set actually changes, making this comparison cheap and exact.
 const rowsChanged = !prev || prev[0] !== keys || prev[2] !== curr[2]
 if (rowsChanged) virtualizer.scrollToIndex(keys.length - 1, { align: "end" })
 scheduleMeasuredBottomAnchor()
 },
 { defer: true },
Expand Down

14 changes: 14 additions & 0 deletions
packages/ui/src/components/message-part.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -60,6 +60,9 @@ import { useLocation } from "@solidjs/router"
import { attached, inline, kind } from "./message-file"
import { readPartText } from "./message-part-text"

const reducedMotion = () =>
 typeof window !== "undefined" && !!window.matchMedia?.("(prefers-reduced-motion: reduce)").matches

async function writeClipboard(text: string): Promise<boolean> {
 const body = typeof document === "undefined" ? undefined : document.body
 if (body) {
Expand DownExpand Up@@ -90,6 +93,17 @@ function ShellSubmessage(props: { text: string; animate?: boolean }) {

 onMount(() => {
 if (!props.animate) return
 // The initial render collapses width to 0 and hides the value behind a blur;
 // if the user prefers reduced motion, snap straight to the resting state
 // instead of animating (and instead of leaving it stuck collapsed/hidden).
 if (reducedMotion()) {
 if (widthRef) widthRef.style.width = "auto"
 if (valueRef) {
 valueRef.style.opacity = "1"
 valueRef.style.filter = "blur(0px)"
 }
 return
 }
 requestAnimationFrame(() => {
 if (widthRef) {
 animate(widthRef, { width: "auto" }, { type: "spring", visualDuration: 0.25, bounce: 0 })
Expand Down
Loading