EventTarget removeEventListener does not match all listeners #65244

Closed
#65245
Closed
EventTarget removeEventListener does not match all listeners#65244
#65245
Labels
eventsIssues and PRs related to EventEmitter and the events module.

Description

@achingbrain
achingbrain
opened on Aug 12, 2026

Version

v26.7.0

Platform

Darwin Mac.localdomain 25.5.0 Darwin Kernel Version 25.5.0: Mon Apr 27 20:41:15 PDT 2026; root:xnu-12377.121.6~2/RELEASE_ARM64_T6041 arm64

Subsystem

events

What steps will reproduce the bug?

letinvocations=0constlistener=()=>{invocations++}consttarget=newEventTarget()// add the listenertarget.addEventListener('test',listener,true)// remove the listenertarget.removeEventListener('test',listener,true)// dispatch an eventtarget.dispatchEvent(newEvent('test'))// invocations should be 0console.info('invocations',invocations)

How often does it reproduce? Is there a required condition?

Every time.

What is the expected behavior? Why is that the expected behavior?

All matching event listeners should be removed, invocations should be 0.

What do you see instead?

The event listener is not removed, invocations is 1.

Additional information

Running the code under Node.js and popular browsers results in differing output. Chrome, Firefox and Safari all print 0, Node.js prints 1.

This can cause memory leaks, unexpected application behaviour, etc.

Activity

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      , '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
      EventTarget removeEventListener does not match all listeners #65244
      Closed
      #65245
      Closed
      EventTarget removeEventListener does not match all listeners#65244
      #65245
      Labels
      eventsIssues and PRs related to EventEmitter and the events module.
      Description
      @achingbrain
      achingbrain
      opened on Aug 12, 2026
      Version
      v26.7.0
      Platform
      Darwin Mac.localdomain 25.5.0 Darwin Kernel Version 25.5.0: Mon Apr 27 20:41:15 PDT 2026; root:xnu-12377.121.6~2/RELEASE_ARM64_T6041 arm64

      Subsystem
      events
      What steps will reproduce the bug?
      letinvocations=0constlistener=()=>{invocations++}consttarget=newEventTarget()// add the listenertarget.addEventListener('test',listener,true)// remove the listenertarget.removeEventListener('test',listener,true)// dispatch an eventtarget.dispatchEvent(newEvent('test'))// invocations should be 0console.info('invocations',invocations)
      How often does it reproduce? Is there a required condition?
      Every time.
      What is the expected behavior? Why is that the expected behavior?
      All matching event listeners should be removed, invocations should be 0.
      What do you see instead?
      The event listener is not removed, invocations is 1.
      Additional information
      Running the code under Node.js and popular browsers results in differing output. Chrome, Firefox and Safari all print 0, Node.js prints 1.
      This can cause memory leaks, unexpected application behaviour, etc.
      Activity
      Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
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      Assignees
      No one assigned
        Labels
        eventsIssues and PRs related to EventEmitter and the events module.
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        No projects
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          No milestone
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          None yet
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          No branches or pull requests
          Issue actions
          
, '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
          EventTarget removeEventListener does not match all listeners #65244
          Closed
          #65245
          Closed
          EventTarget removeEventListener does not match all listeners#65244
          #65245
          Labels
          eventsIssues and PRs related to EventEmitter and the events module.
          Description
          @achingbrain
          achingbrain
          opened on Aug 12, 2026
          Version
          v26.7.0
          Platform
          Darwin Mac.localdomain 25.5.0 Darwin Kernel Version 25.5.0: Mon Apr 27 20:41:15 PDT 2026; root:xnu-12377.121.6~2/RELEASE_ARM64_T6041 arm64

          Subsystem
          events
          What steps will reproduce the bug?
          letinvocations=0constlistener=()=>{invocations++}consttarget=newEventTarget()// add the listenertarget.addEventListener('test',listener,true)// remove the listenertarget.removeEventListener('test',listener,true)// dispatch an eventtarget.dispatchEvent(newEvent('test'))// invocations should be 0console.info('invocations',invocations)
          How often does it reproduce? Is there a required condition?
          Every time.
          What is the expected behavior? Why is that the expected behavior?
          All matching event listeners should be removed, invocations should be 0.
          What do you see instead?
          The event listener is not removed, invocations is 1.
          Additional information
          Running the code under Node.js and popular browsers results in differing output. Chrome, Firefox and Safari all print 0, Node.js prints 1.
          This can cause memory leaks, unexpected application behaviour, etc.
          Activity
          Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
          Metadata
          Metadata
          Assignees
          No one assigned
            Labels
            eventsIssues and PRs related to EventEmitter and the events module.
            Type
            No type
            Projects
            No projects
              Milestone
              No milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, '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
              EventTarget removeEventListener does not match all listeners #65244
              Closed
              #65245
              Closed
              EventTarget removeEventListener does not match all listeners#65244
              #65245
              Labels
              eventsIssues and PRs related to EventEmitter and the events module.
              Description
              @achingbrain
              achingbrain
              opened on Aug 12, 2026
              Version
              v26.7.0
              Platform
              Darwin Mac.localdomain 25.5.0 Darwin Kernel Version 25.5.0: Mon Apr 27 20:41:15 PDT 2026; root:xnu-12377.121.6~2/RELEASE_ARM64_T6041 arm64

              Subsystem
              events
              What steps will reproduce the bug?
              letinvocations=0constlistener=()=>{invocations++}consttarget=newEventTarget()// add the listenertarget.addEventListener('test',listener,true)// remove the listenertarget.removeEventListener('test',listener,true)// dispatch an eventtarget.dispatchEvent(newEvent('test'))// invocations should be 0console.info('invocations',invocations)
              How often does it reproduce? Is there a required condition?
              Every time.
              What is the expected behavior? Why is that the expected behavior?
              All matching event listeners should be removed, invocations should be 0.
              What do you see instead?
              The event listener is not removed, invocations is 1.
              Additional information
              Running the code under Node.js and popular browsers results in differing output. Chrome, Firefox and Safari all print 0, Node.js prints 1.
              This can cause memory leaks, unexpected application behaviour, etc.
              Activity
              Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
              Metadata
              Metadata
              Assignees
              No one assigned
                Labels
                eventsIssues and PRs related to EventEmitter and the events module.
                Type
                No type
                Projects
                No projects
                  Milestone
                  No milestone
                  Relationships
                  None yet
                  Development
                  No branches or pull requests
                  Issue actions
                  
, '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
                  EventTarget removeEventListener does not match all listeners #65244
                  Closed
                  #65245
                  Closed
                  EventTarget removeEventListener does not match all listeners#65244
                  #65245
                  Labels
                  eventsIssues and PRs related to EventEmitter and the events module.
                  Description
                  @achingbrain
                  achingbrain
                  opened on Aug 12, 2026
                  Version
                  v26.7.0
                  Platform
                  Darwin Mac.localdomain 25.5.0 Darwin Kernel Version 25.5.0: Mon Apr 27 20:41:15 PDT 2026; root:xnu-12377.121.6~2/RELEASE_ARM64_T6041 arm64

                  Subsystem
                  events
                  What steps will reproduce the bug?
                  letinvocations=0constlistener=()=>{invocations++}consttarget=newEventTarget()// add the listenertarget.addEventListener('test',listener,true)// remove the listenertarget.removeEventListener('test',listener,true)// dispatch an eventtarget.dispatchEvent(newEvent('test'))// invocations should be 0console.info('invocations',invocations)
                  How often does it reproduce? Is there a required condition?
                  Every time.
                  What is the expected behavior? Why is that the expected behavior?
                  All matching event listeners should be removed, invocations should be 0.
                  What do you see instead?
                  The event listener is not removed, invocations is 1.
                  Additional information
                  Running the code under Node.js and popular browsers results in differing output. Chrome, Firefox and Safari all print 0, Node.js prints 1.
                  This can cause memory leaks, unexpected application behaviour, etc.
                  Activity
                  Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
                  Metadata
                  Metadata
                  Assignees
                  No one assigned
                    Labels
                    eventsIssues and PRs related to EventEmitter and the events module.
                    Type
                    No type
                    Projects
                    No projects
                      Milestone
                      No milestone
                      Relationships
                      None yet
                      Development
                      No branches or pull requests
                      Issue actions
                      
, '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
                      EventTarget removeEventListener does not match all listeners #65244
                      Closed
                      #65245
                      Closed
                      EventTarget removeEventListener does not match all listeners#65244
                      #65245
                      Labels
                      eventsIssues and PRs related to EventEmitter and the events module.
                      Description
                      @achingbrain
                      achingbrain
                      opened on Aug 12, 2026
                      Version
                      v26.7.0
                      Platform
                      Darwin Mac.localdomain 25.5.0 Darwin Kernel Version 25.5.0: Mon Apr 27 20:41:15 PDT 2026; root:xnu-12377.121.6~2/RELEASE_ARM64_T6041 arm64

                      Subsystem
                      events
                      What steps will reproduce the bug?
                      letinvocations=0constlistener=()=>{invocations++}consttarget=newEventTarget()// add the listenertarget.addEventListener('test',listener,true)// remove the listenertarget.removeEventListener('test',listener,true)// dispatch an eventtarget.dispatchEvent(newEvent('test'))// invocations should be 0console.info('invocations',invocations)
                      How often does it reproduce? Is there a required condition?
                      Every time.
                      What is the expected behavior? Why is that the expected behavior?
                      All matching event listeners should be removed, invocations should be 0.
                      What do you see instead?
                      The event listener is not removed, invocations is 1.
                      Additional information
                      Running the code under Node.js and popular browsers results in differing output. Chrome, Firefox and Safari all print 0, Node.js prints 1.
                      This can cause memory leaks, unexpected application behaviour, etc.
                      Activity
                      Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
                      Metadata
                      Metadata
                      Assignees
                      No one assigned
                        Labels
                        eventsIssues and PRs related to EventEmitter and the events module.
                        Type
                        No type
                        Projects
                        No projects
                          Milestone
                          No milestone
                          Relationships
                          None yet
                          Development
                          No branches or pull requests
                          Issue actions
                          
, '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
                          EventTarget removeEventListener does not match all listeners #65244
                          Closed
                          #65245
                          Closed
                          EventTarget removeEventListener does not match all listeners#65244
                          #65245
                          Labels
                          eventsIssues and PRs related to EventEmitter and the events module.
                          Description
                          @achingbrain
                          achingbrain
                          opened on Aug 12, 2026
                          Version
                          v26.7.0
                          Platform
                          Darwin Mac.localdomain 25.5.0 Darwin Kernel Version 25.5.0: Mon Apr 27 20:41:15 PDT 2026; root:xnu-12377.121.6~2/RELEASE_ARM64_T6041 arm64

                          Subsystem
                          events
                          What steps will reproduce the bug?
                          letinvocations=0constlistener=()=>{invocations++}consttarget=newEventTarget()// add the listenertarget.addEventListener('test',listener,true)// remove the listenertarget.removeEventListener('test',listener,true)// dispatch an eventtarget.dispatchEvent(newEvent('test'))// invocations should be 0console.info('invocations',invocations)
                          How often does it reproduce? Is there a required condition?
                          Every time.
                          What is the expected behavior? Why is that the expected behavior?
                          All matching event listeners should be removed, invocations should be 0.
                          What do you see instead?
                          The event listener is not removed, invocations is 1.
                          Additional information
                          Running the code under Node.js and popular browsers results in differing output. Chrome, Firefox and Safari all print 0, Node.js prints 1.
                          This can cause memory leaks, unexpected application behaviour, etc.
                          Activity
                          Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
                          Metadata
                          Metadata
                          Assignees
                          No one assigned
                            Labels
                            eventsIssues and PRs related to EventEmitter and the events module.
                            Type
                            No type
                            Projects
                            No projects
                              Milestone
                              No milestone
                              Relationships
                              None yet
                              Development
                              No branches or pull requests
                              Issue actions
                              
, '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
                              EventTarget removeEventListener does not match all listeners #65244
                              Closed
                              #65245
                              Closed
                              EventTarget removeEventListener does not match all listeners#65244
                              #65245
                              Labels
                              eventsIssues and PRs related to EventEmitter and the events module.
                              Description
                              @achingbrain
                              achingbrain
                              opened on Aug 12, 2026
                              Version
                              v26.7.0
                              Platform
                              Darwin Mac.localdomain 25.5.0 Darwin Kernel Version 25.5.0: Mon Apr 27 20:41:15 PDT 2026; root:xnu-12377.121.6~2/RELEASE_ARM64_T6041 arm64

                              Subsystem
                              events
                              What steps will reproduce the bug?
                              letinvocations=0constlistener=()=>{invocations++}consttarget=newEventTarget()// add the listenertarget.addEventListener('test',listener,true)// remove the listenertarget.removeEventListener('test',listener,true)// dispatch an eventtarget.dispatchEvent(newEvent('test'))// invocations should be 0console.info('invocations',invocations)
                              How often does it reproduce? Is there a required condition?
                              Every time.
                              What is the expected behavior? Why is that the expected behavior?
                              All matching event listeners should be removed, invocations should be 0.
                              What do you see instead?
                              The event listener is not removed, invocations is 1.
                              Additional information
                              Running the code under Node.js and popular browsers results in differing output. Chrome, Firefox and Safari all print 0, Node.js prints 1.
                              This can cause memory leaks, unexpected application behaviour, etc.
                              Activity
                              Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
                              Metadata
                              Metadata
                              Assignees
                              No one assigned
                                Labels
                                eventsIssues and PRs related to EventEmitter and the events module.
                                Type
                                No type
                                Projects
                                No projects
                                  Milestone
                                  No milestone
                                  Relationships
                                  None yet
                                  Development
                                  No branches or pull requests
                                  Issue actions