bugzilla-data-low.json

{"bugs":[{"status":"ASSIGNED","summary":"Stop looking up GLContext symbols for every new window","op_sys":"Unspecified","severity":"S3","creation_time":"2017-02-22T23:15:05Z","component":"Graphics","last_change_time":"2025-04-24T15:29:17Z","priority":"P3","keywords":["perf"],"id":1341913},{"status":"ASSIGNED","severity":"S3","summary":"Delayed image loading on low end ARM devices","op_sys":"Android","creation_time":"2019-01-23T21:52:44Z","last_change_time":"2025-03-21T02:42:31Z","component":"Performance: Navigation","keywords":["perf:pageload"],"priority":"P1","id":1522282},{"creation_time":"2020-04-21T20:52:29Z","component":"Graphics","last_change_time":"2022-10-12T00:08:45Z","keywords":["perf:startup"],"priority":"P3","id":1631949,"status":"ASSIGNED","summary":"Investigate merging shader cache files","op_sys":"Unspecified","severity":"S3"},{"severity":"S3","op_sys":"Android","summary":"Firefox 113.2.0 at Android 13. Audio and video stutter when using bluetooth output.","status":"ASSIGNED","keywords":[],"priority":"P2","id":1835986,"creation_time":"2023-05-31T08:02:46Z","last_change_time":"2026-04-01T00:29:04Z","component":"Audio/Video: Playback"},{"component":"Graphics: Text","last_change_time":"2026-06-18T14:36:07Z","creation_time":"2026-01-05T20:54:42Z","id":2008619,"keywords":["meta"],"priority":"--","status":"ASSIGNED","summary":"[meta] Text shaping word cache affects performance on several SP3 tests (particularly TipTap)","op_sys":"Unspecified","severity":"S2"},{"status":"NEW","op_sys":"Windows Vista","summary":"Poor performance using bookmarks menu with large amounts of bookmarks.","severity":"S3","creation_time":"2009-04-01T20:00:41Z","component":"Bookmarks & History","last_change_time":"2023-05-16T02:23:47Z","keywords":["blocked-ux","perf"],"priority":"P3","id":486378},{"last_change_time":"2025-03-11T07:58:22Z","component":"Places","creation_time":"2009-04-29T22:35:30Z","id":490714,"priority":"P3","keywords":["main-thread-io","meta","perf","perf:frontend","perf:responsiveness"],"status":"NEW","severity":"N/A","summary":"[meta] Implement an Asynchronous API for opening container query nodes","op_sys":"All"},{"priority":"--","keywords":["perf","perf:responsiveness","testcase"],"id":575614,"creation_time":"2010-06-29T14:36:04Z","component":"Layout: Columns","last_change_time":"2022-10-10T22:59:55Z","op_sys":"All","summary":"{inc} Resizing window is slow for long list with multicol (from \"-moz-column-count: 3\" or \"column-width: 20em;\")","severity":"S3","status":"NEW"},{"keywords":["perf","perf:pageload"],"priority":"--","id":613498,"creation_time":"2010-11-19T15:34:28Z","last_change_time":"2025-03-11T08:46:07Z","component":"XPConnect","severity":"S3","op_sys":"macOS","summary":"Very slow chrome to content DOM access","status":"NEW"},{"keywords":["perf","perf:resource-use"],"priority":"P3","id":646937,"creation_time":"2011-03-31T18:37:55Z","last_change_time":"2022-10-10T23:24:13Z","component":"Widget","severity":"S3","op_sys":"Linux","summary":"throttle animation in completely obscured windows (virtual desktop, minimised, hidden behind other fullscreened windows)","status":"NEW"},{"status":"NEW","op_sys":"All","summary":"Repeated calls to location.hash = \"#foo\" cause large amounts of disk activity","severity":"S3","component":"Places","last_change_time":"2025-09-29T14:01:38Z","creation_time":"2011-06-02T18:09:59Z","id":661590,"keywords":["perf","perf:responsiveness"],"priority":"P3"},{"status":"NEW","op_sys":"All","summary":"Compositing/present still hapens when the only changing parts are out of the viewport","severity":"S3","creation_time":"2011-12-19T09:05:20Z","component":"Graphics: WebRender","last_change_time":"2024-04-08T16:58:41Z","keywords":["perf","perf:resource-use"],"priority":"--","id":711924},{"creation_time":"2012-06-03T03:18:54Z","last_change_time":"2024-04-05T11:37:58Z","component":"Graphics: Canvas2D","priority":"--","keywords":["perf"],"id":760888,"status":"NEW","severity":"S3","op_sys":"All","summary":"IE10 Test Drive: ParticleAcceleration Canvas 2D demo is slow"},{"severity":"S3","op_sys":"All","summary":"We appear to be copying large data URIs over and over in nsSimpleURI.","status":"NEW","priority":"P3","keywords":["perf:resource-use"],"id":803709,"creation_time":"2012-10-19T21:25:22Z","last_change_time":"2023-06-05T16:31:57Z","component":"Networking"},{"component":"PDF Viewer","last_change_time":"2025-03-31T14:05:54Z","creation_time":"2012-11-09T08:29:30Z","id":810214,"priority":"P3","keywords":["perf:responsiveness"],"status":"NEW","op_sys":"Linux","summary":"Processing http://lib.tkk.fi/Dipl/2002/urn007413.pdf is slow, and its text layer is all messed up","severity":"S3"},{"component":"CSS Parsing and Computation","last_change_time":"2023-03-01T12:04:23Z","creation_time":"2012-12-14T13:46:12Z","id":821693,"keywords":["perf","perf:responsiveness"],"priority":"--","status":"NEW","summary":"janky Scrolling on smartsheet.com Sheets","op_sys":"Windows 7","severity":"S3"},{"status":"NEW","severity":"S3","op_sys":"Windows 7","summary":"nsIconChannel::AsyncOpen can block","last_change_time":"2022-11-24T06:34:31Z","component":"Graphics: ImageLib","creation_time":"2013-01-07T19:06:03Z","id":827440,"priority":"--","keywords":["perf"]},{"id":827937,"keywords":["perf"],"priority":"--","last_change_time":"2022-10-29T12:12:42Z","component":"Layout","creation_time":"2013-01-08T19:17:33Z","severity":"S3","summary":"Opening huge mercurial long commit page freezing Firefox","op_sys":"Windows 8","status":"NEW"},{"severity":"S3","summary":"Firefox should abort on tryserver when executing SQL on the main thread","op_sys":"All","status":"NEW","priority":"P3","keywords":["perf:frontend","perf:responsiveness"],"id":830504,"creation_time":"2013-01-14T22:07:19Z","last_change_time":"2024-08-20T19:28:43Z","component":"SQLite and Embedded Database Bindings"},{"status":"NEW","severity":"S3","op_sys":"All","summary":"Use IOUtils for gLastOpenDirectory","creation_time":"2013-02-05T02:16:08Z","last_change_time":"2023-05-16T02:22:53Z","component":"General","priority":"--","keywords":["main-thread-io","perf:frontend"],"id":837989},{"last_change_time":"2024-03-27T16:10:09Z","component":"Networking: File","creation_time":"2013-04-16T15:29:21Z","id":862383,"priority":"P3","keywords":["main-thread-io","perf:responsiveness"],"status":"NEW","severity":"S3","summary":"nsFileChannel::nsFileChannel causes expensive lstats","op_sys":"macOS"},{"summary":"nsIOService::NewFileURI is doing main thread IO and causes jank","op_sys":"All","severity":"S3","status":"NEW","id":890712,"priority":"P3","keywords":["main-thread-io","perf","perf:frontend"],"component":"Networking","last_change_time":"2024-04-01T16:26:36Z","creation_time":"2013-07-07T15:57:11Z"},{"creation_time":"2013-09-10T12:49:00Z","component":"Layout","last_change_time":"2023-07-27T07:06:57Z","priority":"--","keywords":["perf"],"id":914595,"status":"NEW","summary":"Polygon.com page scrolling becomes extremely slow after a while","op_sys":"All","severity":"S3"},{"status":"NEW","severity":"S3","summary":"Visibility state is not updated when the browser window is obscured or on another workspace","op_sys":"All","creation_time":"2013-09-17T02:34:03Z","last_change_time":"2022-10-11T01:07:35Z","component":"General","priority":"--","keywords":["perf:resource-use"],"id":917090},{"status":"NEW","severity":"S3","summary":"Optimize GetRootPresContext() to avoid going through the viewmanager / view tree","op_sys":"Linux","last_change_time":"2025-12-02T04:57:52Z","component":"Layout","creation_time":"2014-03-18T00:14:52Z","id":984690,"keywords":["perf"],"priority":"--"},{"status":"NEW","summary":"Preload panel contents on hover of toolbar button","op_sys":"All","severity":"S3","component":"Toolbars and Customization","last_change_time":"2023-07-19T04:52:40Z","creation_time":"2014-06-10T10:02:00Z","id":1023152,"priority":"--","keywords":["perf:frontend"]},{"status":"NEW","summary":"Make bookmarks toolbar view use async openContainer","op_sys":"All","severity":"S3","creation_time":"2014-08-02T09:50:40Z","component":"Places","last_change_time":"2026-05-29T15:38:01Z","priority":"P3","keywords":["perf:frontend"],"id":1047817},{"last_change_time":"2022-10-11T15:57:30Z","component":"JavaScript Engine","creation_time":"2014-11-12T00:22:19Z","id":1097376,"keywords":["perf"],"priority":"--","status":"NEW","severity":"S3","summary":"Poor performance in Ember app Discourse","op_sys":"Android"},{"status":"NEW","op_sys":"All","summary":"[e10s] There is a delay for about 1 seconds to display <select> drop-down list with 1600+ items","severity":"S3","component":"Layout: Form Controls","last_change_time":"2025-12-05T02:06:49Z","creation_time":"2015-01-06T01:55:10Z","id":1118086,"keywords":["multiprocess","perf","perf:responsiveness","testcase"],"priority":"P5"},{"id":1154987,"priority":"--","keywords":["meta","perf"],"last_change_time":"2026-04-07T07:26:45Z","component":"JavaScript Engine","creation_time":"2015-04-15T23:32:29Z","severity":"S3","summary":"[Meta] Move JS parsing off of main thread and enable incremental parsing","op_sys":"Windows 8.1","status":"NEW"},{"summary":"Very laggy panning and zooming of map on Orbis website","op_sys":"All","severity":"S3","status":"NEW","keywords":["perf:animation","perf:responsiveness","reproducible"],"priority":"--","id":1155307,"creation_time":"2015-04-16T18:22:07Z","component":"Graphics: WebRender","last_change_time":"2024-04-02T23:00:44Z"},{"op_sys":"Unspecified","summary":"ES6 Map performance for large numbers of elements is deficient","severity":"S3","status":"NEW","id":1162665,"keywords":[],"priority":"--","component":"JavaScript: GC","last_change_time":"2025-03-12T05:36:53Z","creation_time":"2015-05-07T18:46:57Z"},{"id":1213513,"priority":"--","keywords":["perf:responsiveness"],"last_change_time":"2023-02-19T05:13:03Z","component":"DOM: Animation","creation_time":"2015-10-10T00:31:34Z","severity":"S3","summary":"2D canvas+HTML/CSS animation demo site broken on Firefox, works great on Chrome","op_sys":"Unspecified","status":"NEW"},{"creation_time":"2015-10-23T09:20:20Z","last_change_time":"2024-09-22T12:08:26Z","component":"Layout","keywords":[],"priority":"--","id":1217748,"status":"NEW","severity":"S3","summary":"On/Off opacity changes shouldn't create active layers","op_sys":"All"},{"id":1222086,"priority":"--","keywords":["perf"],"component":"JavaScript 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x2go","severity":"S3","component":"Graphics","last_change_time":"2022-12-08T15:45:06Z","creation_time":"2016-06-29T13:06:59Z","id":1283089,"priority":"P3","keywords":["perf:responsiveness","regression"]},{"status":"NEW","summary":"Try to tick refresh driver during html parsing","op_sys":"Unspecified","severity":"S3","creation_time":"2016-08-12T05:51:58Z","component":"Layout","last_change_time":"2026-06-10T12:53:35Z","keywords":["perf"],"priority":"P3","id":1294625},{"status":"NEW","summary":"Measure and solve sync reflow for studying gdoc performance.","op_sys":"Unspecified","severity":"S3","creation_time":"2016-08-18T03:04:45Z","component":"Layout","last_change_time":"2022-10-11T18:31:41Z","keywords":["perf"],"priority":"P3","id":1296161},{"severity":"S3","summary":"If you set a high Polling Rate USB port of the mouse (1000 Hz), there will be noticeable performance issues while moving tabs","op_sys":"Windows 7","status":"NEW","priority":"--","keywords":["perf"],"id":1306925,"creation_time":"2016-10-01T23:51:50Z","last_change_time":"2026-02-17T17:22:57Z","component":"Widget: Win32"},{"creation_time":"2016-10-03T03:00:35Z","last_change_time":"2024-08-14T04:57:13Z","component":"General","priority":"--","keywords":["perf"],"id":1307024,"status":"NEW","severity":"S3","summary":"[Perf] [google docs] Firefox will get 3~9% faster when running gdoc test cases with chrome user agent","op_sys":"Linux"},{"creation_time":"2016-10-08T00:18:22Z","component":"Layout","last_change_time":"2025-04-16T19:29:34Z","keywords":["perf","perf:responsiveness"],"priority":"--","id":1308660,"status":"NEW","summary":"for background tabs, break refresh driver tick into multiple events off the main thread's event loop","op_sys":"Unspecified","severity":"--"},{"status":"NEW","severity":"S3","summary":"Google Apps extremely slow -- scrolling, updating text, etc -- unusable","op_sys":"Windows 10","last_change_time":"2022-10-11T18:44:06Z","component":"JavaScript Engine","creation_time":"2016-11-11T14:41:11Z","id":1316864,"priority":"P5","keywords":["perf"]},{"status":"NEW","summary":"[meta] Speed and performance of importing bookmarks from JSON or HTML files is awful","op_sys":"All","severity":"--","creation_time":"2016-11-27T11:13:21Z","component":"Bookmarks & History","last_change_time":"2025-03-11T08:30:57Z","keywords":["hang","meta","nightly-community","perf:frontend"],"priority":"P5","id":1320534},{"component":"Layout","last_change_time":"2025-03-11T07:51:38Z","creation_time":"2017-01-11T03:23:20Z","id":1330187,"keywords":["perf:resource-use"],"priority":"P3","status":"NEW","summary":"DisplayList building shows signs of poor CPU usage","op_sys":"Unspecified","severity":"S3"},{"creation_time":"2017-01-12T08:37:41Z","component":"Layout","last_change_time":"2022-10-11T18:55:13Z","keywords":["perf:resource-use"],"priority":"P3","id":1330558,"status":"NEW","op_sys":"Unspecified","summary":"Explore using the presshell arena for FramePropertyTable","severity":"S3"},{"priority":"P3","keywords":["hang","perf"],"id":1334655,"creation_time":"2017-01-27T21:15:19Z","last_change_time":"2022-10-11T18:58:09Z","component":"Graphics: Layers","severity":"S3","op_sys":"Unspecified","summary":"PCompositorBridge::Msg_WillClose can block the UI thread when closing a window","status":"NEW"},{"id":1341882,"priority":"P3","keywords":["perf"],"last_change_time":"2022-10-11T19:02:26Z","component":"Graphics","creation_time":"2017-02-22T22:05:51Z","severity":"S3","op_sys":"Unspecified","summary":"Slow performance at drawing rectangles on Google Slides","status":"NEW"},{"severity":"S3","summary":"Speed up PHttpChannelConstructor and consider streaming HttpChannelOpenArgs","op_sys":"Unspecified","status":"NEW","id":1342632,"priority":"P3","keywords":["perf"],"last_change_time":"2022-03-02T15:55:52Z","component":"Networking: HTTP","creation_time":"2017-02-25T04:45:01Z"},{"keywords":["perf"],"priority":"P3","id":1343383,"creation_time":"2017-02-28T23:07:56Z","component":"Graphics: Layers","last_change_time":"2022-10-11T19:03:23Z","op_sys":"Unspecified","summary":"nsIDOMWindowUtils::StartFrameTimeRecording should not use sync IPC","severity":"S3","status":"NEW"},{"severity":"S3","summary":"Overpainting on Google docs","op_sys":"Unspecified","status":"NEW","priority":"--","keywords":["perf","perf:responsiveness"],"id":1343538,"creation_time":"2017-03-01T15:26:14Z","last_change_time":"2024-11-22T02:22:00Z","component":"Web Painting"},{"summary":"Consider compiling Ion IC code less eagerly","op_sys":"All","severity":"S3","status":"NEW","priority":"P3","keywords":["perf"],"id":1346178,"creation_time":"2017-03-10T12:17:59Z","component":"JavaScript Engine: JIT","last_change_time":"2025-04-30T01:31:39Z"},{"severity":"S3","summary":"Replace PVRManager::GetSensorState with lock-free shared memory structure (Eliminating message queue IPC)","op_sys":"Unspecified","status":"NEW","id":1346927,"priority":"--","keywords":["perf"],"last_change_time":"2022-10-11T19:05:40Z","component":"WebVR","creation_time":"2017-03-13T20:32:12Z"},{"op_sys":"Unspecified","summary":"Consider storing hints during syntax parse","severity":"S3","status":"NEW","priority":"P5","keywords":["perf"],"id":1347861,"creation_time":"2017-03-16T09:28:24Z","component":"JavaScript Engine","last_change_time":"2022-10-11T19:06:12Z"},{"id":1348697,"priority":"--","keywords":["perf"],"last_change_time":"2023-11-27T10:28:31Z","component":"Layout","creation_time":"2017-03-19T22:26:30Z","severity":"S3","summary":"Optimize away OverflowAreasProperty more often","op_sys":"All","status":"NEW"},{"priority":"P3","keywords":["perf"],"id":1349148,"creation_time":"2017-03-21T09:28:43Z","last_change_time":"2024-04-24T02:40:50Z","component":"JavaScript Engine: JIT","severity":"S3","op_sys":"All","summary":"Improve performance of megamorphic stubs","status":"NEW"},{"id":1350367,"priority":"P3","keywords":["perf"],"component":"DOM: Service Workers","last_change_time":"2022-10-11T19:08:05Z","creation_time":"2017-03-24T15:40:46Z","summary":"Make service worker ScriptLoader paths use cached js bytecode from cache API","op_sys":"Unspecified","severity":"S3","status":"NEW"},{"id":1350569,"priority":"--","keywords":["perf:frontend"],"last_change_time":"2023-07-19T04:57:18Z","component":"Session Restore","creation_time":"2017-03-25T15:19:03Z","severity":"S3","summary":"Avoid full session history collect for DOMTitleChanged/OnHistoryReload","op_sys":"Unspecified","status":"NEW"},{"status":"NEW","severity":"S3","summary":"Bad performance on Sony Horizon game page","op_sys":"Unspecified","creation_time":"2017-03-25T21:49:47Z","last_change_time":"2022-10-11T19:08:17Z","component":"Audio/Video: Playback","priority":"P3","keywords":["perf"],"id":1350618},{"status":"NEW","op_sys":"Unspecified","summary":"Add some instrumentation to find commonly added preference observers","severity":"S3","component":"General","last_change_time":"2022-10-11T19:08:21Z","creation_time":"2017-03-26T21:54:08Z","id":1350749,"priority":"--","keywords":["perf"]},{"creation_time":"2017-03-29T17:44:37Z","component":"Performance: General","last_change_time":"2025-03-11T08:37:03Z","priority":"--","keywords":["nightly-community","perf","perf:resource-use","power"],"id":1351755,"status":"NEW","summary":"Provide \"Slight/Light/Low power/Battery saving/Battery saver\" mode option","op_sys":"All","severity":"--"},{"status":"NEW","severity":"S3","op_sys":"Unspecified","summary":"Add Telemetry probes for measuring garbage volume per GC","creation_time":"2017-03-29T18:30:44Z","last_change_time":"2025-04-27T11:43:06Z","component":"JavaScript: GC","priority":"P3","keywords":["perf"],"id":1351789},{"summary":"Consider faster alternatives to PLDHashTable in hot Layout code paths","op_sys":"All","severity":"S3","status":"NEW","id":1351829,"keywords":["perf"],"priority":"--","component":"Layout","last_change_time":"2022-10-11T19:09:06Z","creation_time":"2017-03-29T20:02:58Z"},{"creation_time":"2017-03-29T20:09:00Z","last_change_time":"2025-05-05T12:26:28Z","component":"Layout","keywords":["perf"],"priority":"--","id":1351830,"status":"NEW","severity":"S3","op_sys":"All","summary":"Consider adding StyleDisplay() values to nsIFrame"},{"id":1352205,"keywords":["perf","perf:resource-use"],"priority":"P2","last_change_time":"2022-11-02T13:08:34Z","component":"Layout","creation_time":"2017-03-30T20:21:31Z","severity":"--","op_sys":"Unspecified","summary":"Avoid running the refresh driver when the page is in background","status":"NEW"},{"status":"NEW","severity":"S3","op_sys":"Unspecified","summary":"[meta] Improve GC scheduling","last_change_time":"2025-05-06T16:14:08Z","component":"JavaScript: GC","creation_time":"2017-03-31T19:02:50Z","id":1352524,"keywords":["meta","perf"],"priority":"P3"},{"severity":"S3","op_sys":"All","summary":"Optimize GetName TypeOfNoProperty","status":"NEW","id":1353384,"keywords":["perf"],"priority":"P3","last_change_time":"2025-02-10T18:11:27Z","component":"JavaScript Engine: JIT","creation_time":"2017-04-04T14:54:51Z"},{"id":1354945,"keywords":["perf"],"priority":"P3","component":"XPConnect","last_change_time":"2022-10-11T19:11:14Z","creation_time":"2017-04-09T22:09:43Z","op_sys":"Unspecified","summary":"Initialize sandbox global properties lazily","severity":"S3","status":"NEW"},{"status":"NEW","severity":"S3","op_sys":"Unspecified","summary":"Investigate preparing the next tab on mousedown on the tab close button","creation_time":"2017-04-11T13:02:53Z","last_change_time":"2023-07-19T04:59:14Z","component":"Tabbed Browser","priority":"P3","keywords":["perf","perf:frontend","perf:responsiveness"],"id":1355456},{"id":1355459,"priority":"P4","keywords":["perf:frontend"],"last_change_time":"2023-05-16T02:22:12Z","component":"General","creation_time":"2017-04-11T13:07:05Z","severity":"S3","summary":"The last window and the task bar item should disappear immediately on shutdown","op_sys":"Unspecified","status":"NEW"},{"id":1356532,"keywords":["perf:frontend","perf:responsiveness"],"priority":"P3","last_change_time":"2024-03-22T08:25:52Z","component":"Autocomplete","creation_time":"2017-04-14T09:29:21Z","severity":"S3","op_sys":"Unspecified","summary":"Try avoiding layout flushes in autocomplete::_handleOverflow","status":"NEW"},{"status":"NEW","op_sys":"Unspecified","summary":"Rewrite AppConstants.jsm in 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on Firefox likely due to hidden loading spinners","severity":"S3","creation_time":"2019-09-27T02:18:23Z","component":"SVG","last_change_time":"2025-03-11T07:05:48Z","priority":"P3","keywords":["perf:resource-use"],"id":1584418},{"component":"XPCOM","last_change_time":"2022-10-11T23:25:33Z","creation_time":"2019-10-07T15:49:31Z","id":1586808,"keywords":["main-thread-io","perf"],"priority":"--","status":"NEW","summary":"GetProductDirectory does too much mainthread IO","op_sys":"Unspecified","severity":"S3"},{"last_change_time":"2023-02-23T12:47:47Z","component":"Graphics","creation_time":"2019-10-08T10:57:40Z","id":1587040,"priority":"P3","keywords":["perf:resource-use"],"status":"NEW","severity":"S3","summary":"VSync firing 255 times more frequently than normal during \"display off\" sleep on Windows","op_sys":"Windows"},{"creation_time":"2019-10-16T13:13:10Z","last_change_time":"2023-09-21T16:25:22Z","component":"File 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