bugzilla-data-low.json

{"bugs":[{"keywords":["perf"],"priority":"P3","status":"ASSIGNED","summary":"Stop looking up GLContext symbols for every new window","op_sys":"Unspecified","component":"Graphics","creation_time":"2017-02-22T23:15:05Z","last_change_time":"2025-04-24T15:29:17Z","id":1341913,"severity":"S3"},{"summary":"Delayed image loading on low end ARM devices","op_sys":"Android","priority":"P1","keywords":["perf:pageload"],"status":"ASSIGNED","severity":"S3","creation_time":"2019-01-23T21:52:44Z","component":"Performance: Navigation","last_change_time":"2025-03-21T02:42:31Z","id":1522282},{"summary":"Investigate merging shader cache files","op_sys":"Unspecified","priority":"P3","keywords":["perf:startup"],"status":"ASSIGNED","severity":"S3","id":1631949,"last_change_time":"2022-10-12T00:08:45Z","component":"Graphics","creation_time":"2020-04-21T20:52:29Z"},{"summary":"Text shaping word cache adds a lot of overhead during 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Columns","creation_time":"2010-06-29T14:36:04Z","severity":"S3","status":"NEW","priority":"--","keywords":["perf","perf:responsiveness","testcase"],"summary":"{inc} Resizing window is slow for long list with multicol (from \"-moz-column-count: 3\" or \"column-width: 20em;\")","op_sys":"All"},{"severity":"S3","id":613498,"last_change_time":"2025-03-11T08:46:07Z","component":"XPConnect","creation_time":"2010-11-19T15:34:28Z","op_sys":"macOS","summary":"Very slow chrome to content DOM access","status":"NEW","keywords":["perf","perf:pageload"],"priority":"--"},{"severity":"S3","id":646937,"last_change_time":"2022-10-10T23:24:13Z","creation_time":"2011-03-31T18:37:55Z","component":"Widget","op_sys":"Linux","summary":"throttle animation in completely obscured windows (virtual desktop, minimised, hidden behind other fullscreened windows)","priority":"P3","keywords":["perf","perf:resource-use"],"status":"NEW"},{"status":"NEW","priority":"P3","keywords":["perf","perf:responsiveness"],"summary":"Repeated calls to location.hash = \"#foo\" cause large amounts of disk activity","op_sys":"All","last_change_time":"2025-09-29T14:01:38Z","id":661590,"creation_time":"2011-06-02T18:09:59Z","component":"Places","severity":"S3"},{"severity":"S3","id":711924,"last_change_time":"2024-04-08T16:58:41Z","creation_time":"2011-12-19T09:05:20Z","component":"Graphics: WebRender","op_sys":"All","summary":"Compositing/present still hapens when the only changing parts are out of the viewport","status":"NEW","priority":"--","keywords":["perf","perf:resource-use"]},{"last_change_time":"2024-04-05T11:37:58Z","id":760888,"creation_time":"2012-06-03T03:18:54Z","component":"Graphics: Canvas2D","severity":"S3","priority":"--","keywords":["perf"],"status":"NEW","op_sys":"All","summary":"IE10 Test Drive: ParticleAcceleration Canvas 2D demo is slow"},{"priority":"P3","keywords":["perf:resource-use"],"status":"NEW","summary":"We appear to be copying large data URIs over and over in nsSimpleURI.","op_sys":"All","last_change_time":"2023-06-05T16:31:57Z","id":803709,"creation_time":"2012-10-19T21:25:22Z","component":"Networking","severity":"S3"},{"severity":"S3","last_change_time":"2025-03-31T14:05:54Z","id":810214,"component":"PDF Viewer","creation_time":"2012-11-09T08:29:30Z","summary":"Processing http://lib.tkk.fi/Dipl/2002/urn007413.pdf is slow, and its text layer is all messed up","op_sys":"Linux","status":"NEW","priority":"P3","keywords":["perf:responsiveness"]},{"id":821693,"last_change_time":"2023-03-01T12:04:23Z","component":"CSS Parsing and Computation","creation_time":"2012-12-14T13:46:12Z","severity":"S3","status":"NEW","keywords":["perf","perf:responsiveness"],"priority":"--","op_sys":"Windows 7","summary":"janky Scrolling on smartsheet.com Sheets"},{"status":"NEW","keywords":["perf"],"priority":"--","op_sys":"Windows 7","summary":"nsIconChannel::AsyncOpen can block","creation_time":"2013-01-07T19:06:03Z","component":"Graphics: ImageLib","last_change_time":"2022-11-24T06:34:31Z","id":827440,"severity":"S3"},{"severity":"S3","component":"Layout","creation_time":"2013-01-08T19:17:33Z","id":827937,"last_change_time":"2022-10-29T12:12:42Z","op_sys":"Windows 8","summary":"Opening huge mercurial long commit page freezing Firefox","keywords":["perf"],"priority":"--","status":"NEW"},{"op_sys":"All","summary":"Firefox should abort on tryserver when executing SQL on the main thread","keywords":["perf:frontend","perf:responsiveness"],"priority":"P3","status":"NEW","severity":"S3","creation_time":"2013-01-14T22:07:19Z","component":"SQLite and Embedded Database Bindings","id":830504,"last_change_time":"2024-08-20T19:28:43Z"},{"summary":"Use IOUtils for gLastOpenDirectory","op_sys":"All","keywords":["main-thread-io","perf:frontend"],"priority":"--","status":"NEW","severity":"S3","component":"General","creation_time":"2013-02-05T02:16:08Z","last_change_time":"2023-05-16T02:22:53Z","id":837989},{"severity":"S3","id":862383,"last_change_time":"2024-03-27T16:10:09Z","creation_time":"2013-04-16T15:29:21Z","component":"Networking: File","op_sys":"macOS","summary":"nsFileChannel::nsFileChannel causes expensive lstats","status":"NEW","keywords":["main-thread-io","perf:responsiveness"],"priority":"P3"},{"summary":"nsIOService::NewFileURI is doing main thread IO and causes jank","op_sys":"All","keywords":["main-thread-io","perf","perf:frontend"],"priority":"P3","status":"NEW","severity":"S3","component":"Networking","creation_time":"2013-07-07T15:57:11Z","last_change_time":"2024-04-01T16:26:36Z","id":890712},{"creation_time":"2013-09-10T12:49:00Z","component":"Layout","last_change_time":"2023-07-27T07:06:57Z","id":914595,"severity":"S3","status":"NEW","keywords":["perf"],"priority":"--","op_sys":"All","summary":"Polygon.com page scrolling becomes extremely slow after a while"},{"op_sys":"All","summary":"Visibility state is not updated when the browser window is obscured or on another workspace","status":"NEW","priority":"--","keywords":["perf:resource-use"],"severity":"S3","creation_time":"2013-09-17T02:34:03Z","component":"General","id":917090,"last_change_time":"2022-10-11T01:07:35Z"},{"component":"Layout","creation_time":"2014-03-18T00:14:52Z","last_change_time":"2025-12-02T04:57:52Z","id":984690,"severity":"S3","priority":"--","keywords":["perf"],"status":"NEW","summary":"Optimize GetRootPresContext() to avoid going through the viewmanager / view tree","op_sys":"Linux"},{"keywords":["perf:frontend"],"priority":"--","status":"NEW","summary":"Preload panel contents on hover of toolbar button","op_sys":"All","id":1023152,"last_change_time":"2023-07-19T04:52:40Z","component":"Toolbars and Customization","creation_time":"2014-06-10T10:02:00Z","severity":"S3"},{"summary":"Make bookmarks toolbar view use async 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enable incremental parsing","component":"JavaScript Engine","creation_time":"2015-04-15T23:32:29Z","last_change_time":"2023-10-11T11:00:04Z","id":1154987,"severity":"S3"},{"component":"Graphics: WebRender","creation_time":"2015-04-16T18:22:07Z","last_change_time":"2024-04-02T23:00:44Z","id":1155307,"severity":"S3","status":"NEW","keywords":["perf:animation","perf:responsiveness","reproducible"],"priority":"--","op_sys":"All","summary":"Very laggy panning and zooming of map on Orbis website"},{"op_sys":"Unspecified","summary":"ES6 Map performance for large numbers of elements is deficient","keywords":[],"priority":"--","status":"NEW","severity":"S3","id":1162665,"last_change_time":"2025-03-12T05:36:53Z","creation_time":"2015-05-07T18:46:57Z","component":"JavaScript: GC"},{"severity":"S3","id":1213513,"last_change_time":"2023-02-19T05:13:03Z","component":"DOM: Animation","creation_time":"2015-10-10T00:31:34Z","summary":"2D canvas+HTML/CSS animation demo site broken on Firefox, works great on Chrome","op_sys":"Unspecified","keywords":["perf:responsiveness"],"priority":"--","status":"NEW"},{"op_sys":"All","summary":"On/Off opacity changes shouldn't create active layers","priority":"--","keywords":[],"status":"NEW","severity":"S3","id":1217748,"last_change_time":"2024-09-22T12:08:26Z","component":"Layout","creation_time":"2015-10-23T09:20:20Z"},{"op_sys":"Unspecified","summary":"Block JavaScript parser thread when source code characters are not available","status":"NEW","keywords":["perf"],"priority":"--","severity":"S3","creation_time":"2015-11-05T17:44:28Z","component":"JavaScript Engine","id":1222086,"last_change_time":"2022-10-11T17:46:56Z"},{"severity":"S3","component":"Graphics: CanvasWebGL","creation_time":"2016-02-06T17:43:25Z","id":1246410,"last_change_time":"2025-04-05T10:12:20Z","op_sys":"Unspecified","summary":"Low performance of texImage2D with canvas2d and 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Canvas2D","last_change_time":"2022-11-08T00:01:53Z","id":1278554,"severity":"S3"},{"summary":"Angular framework performance test spends 10% in nursery GC","op_sys":"Unspecified","status":"NEW","keywords":["perf"],"priority":"P3","severity":"S3","component":"JavaScript: GC","creation_time":"2016-06-19T13:43:03Z","id":1280802,"last_change_time":"2024-08-11T09:37:57Z"},{"keywords":["perf:responsiveness","regression"],"priority":"P3","status":"NEW","op_sys":"Linux","summary":"Firefox 40+ are very sluggish through x2go","last_change_time":"2022-12-08T15:45:06Z","id":1283089,"component":"Graphics","creation_time":"2016-06-29T13:06:59Z","severity":"S3"},{"summary":"Try to tick refresh driver during html 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performance of importing bookmarks from JSON or HTML files is awful","status":"NEW","keywords":["hang","meta","nightly-community","perf:frontend"],"priority":"P5"},{"priority":"P3","keywords":["perf:resource-use"],"status":"NEW","summary":"DisplayList building shows signs of poor CPU usage","op_sys":"Unspecified","creation_time":"2017-01-11T03:23:20Z","component":"Layout","last_change_time":"2025-03-11T07:51:38Z","id":1330187,"severity":"S3"},{"last_change_time":"2022-10-11T18:55:13Z","id":1330558,"component":"Layout","creation_time":"2017-01-12T08:37:41Z","severity":"S3","status":"NEW","keywords":["perf:resource-use"],"priority":"P3","op_sys":"Unspecified","summary":"Explore using the presshell arena for FramePropertyTable"},{"status":"NEW","keywords":["hang","perf"],"priority":"P3","op_sys":"Unspecified","summary":"PCompositorBridge::Msg_WillClose can block the UI thread when closing a window","creation_time":"2017-01-27T21:15:19Z","component":"Graphics: Layers","last_change_time":"2022-10-11T18:58:09Z","id":1334655,"severity":"S3"},{"id":1341882,"last_change_time":"2022-10-11T19:02:26Z","creation_time":"2017-02-22T22:05:51Z","component":"Graphics","severity":"S3","priority":"P3","keywords":["perf"],"status":"NEW","op_sys":"Unspecified","summary":"Slow performance at drawing rectangles on Google Slides"},{"last_change_time":"2022-03-02T15:55:52Z","id":1342632,"creation_time":"2017-02-25T04:45:01Z","component":"Networking: HTTP","severity":"S3","keywords":["perf"],"priority":"P3","status":"NEW","op_sys":"Unspecified","summary":"Speed up PHttpChannelConstructor and consider streaming HttpChannelOpenArgs"},{"severity":"S3","id":1343383,"last_change_time":"2022-10-11T19:03:23Z","creation_time":"2017-02-28T23:07:56Z","component":"Graphics: Layers","op_sys":"Unspecified","summary":"nsIDOMWindowUtils::StartFrameTimeRecording should not use sync IPC","status":"NEW","keywords":["perf"],"priority":"P3"},{"severity":"S3","creation_time":"2017-03-01T15:26:14Z","component":"Web Painting","id":1343538,"last_change_time":"2024-11-22T02:22:00Z","op_sys":"Unspecified","summary":"Overpainting on Google docs","status":"NEW","keywords":["perf","perf:responsiveness"],"priority":"--"},{"op_sys":"All","summary":"Consider compiling Ion IC code less eagerly","status":"NEW","priority":"P3","keywords":["perf"],"severity":"S3","component":"JavaScript Engine: JIT","creation_time":"2017-03-10T12:17:59Z","id":1346178,"last_change_time":"2025-04-30T01:31:39Z"},{"last_change_time":"2022-10-11T19:05:40Z","id":1346927,"creation_time":"2017-03-13T20:32:12Z","component":"WebVR","severity":"S3","status":"NEW","priority":"--","keywords":["perf"],"op_sys":"Unspecified","summary":"Replace PVRManager::GetSensorState with lock-free shared memory structure (Eliminating message queue IPC)"},{"severity":"S3","last_change_time":"2022-10-11T19:06:12Z","id":1347861,"component":"JavaScript Engine","creation_time":"2017-03-16T09:28:24Z","op_sys":"Unspecified","summary":"Consider storing hints during syntax parse","priority":"P5","keywords":["perf"],"status":"NEW"},{"status":"NEW","keywords":["perf"],"priority":"--","op_sys":"All","summary":"Optimize away OverflowAreasProperty more often","component":"Layout","creation_time":"2017-03-19T22:26:30Z","last_change_time":"2023-11-27T10:28:31Z","id":1348697,"severity":"S3"},{"status":"NEW","priority":"P3","keywords":["perf"],"summary":"Improve performance of megamorphic stubs","op_sys":"All","last_change_time":"2024-04-24T02:40:50Z","id":1349148,"component":"JavaScript Engine: JIT","creation_time":"2017-03-21T09:28:43Z","severity":"S3"},{"severity":"S3","last_change_time":"2022-10-11T19:08:05Z","id":1350367,"component":"DOM: Service Workers","creation_time":"2017-03-24T15:40:46Z","op_sys":"Unspecified","summary":"Make service 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TypeOfNoProperty","id":1353384,"last_change_time":"2025-02-10T18:11:27Z","component":"JavaScript Engine: JIT","creation_time":"2017-04-04T14:54:51Z","severity":"S3"},{"last_change_time":"2022-10-11T19:11:14Z","id":1354945,"creation_time":"2017-04-09T22:09:43Z","component":"XPConnect","severity":"S3","priority":"P3","keywords":["perf"],"status":"NEW","op_sys":"Unspecified","summary":"Initialize sandbox global properties lazily"},{"status":"NEW","priority":"P3","keywords":["perf","perf:frontend","perf:responsiveness"],"summary":"Investigate preparing the next tab on mousedown on the tab close button","op_sys":"Unspecified","last_change_time":"2023-07-19T04:59:14Z","id":1355456,"component":"Tabbed Browser","creation_time":"2017-04-11T13:02:53Z","severity":"S3"},{"creation_time":"2017-04-11T13:07:05Z","component":"General","last_change_time":"2023-05-16T02:22:12Z","id":1355459,"severity":"S3","keywords":["perf:frontend"],"priority":"P4","status":"NEW","op_sys":"Unspecified","summary":"The last window and the task bar item should disappear immediately on shutdown"},{"creation_time":"2017-04-11T13:26:24Z","component":"Widget: Cocoa","id":1355466,"last_change_time":"2022-10-11T19:11:35Z","severity":"S3","status":"NEW","keywords":["perf","perf:responsiveness"],"priority":"P3","op_sys":"macOS","summary":"Activating the browser window is janky"},{"priority":"P3","keywords":["perf:frontend","perf:responsiveness"],"status":"NEW","op_sys":"Unspecified","summary":"Try avoiding layout flushes in autocomplete::_handleOverflow","last_change_time":"2024-03-22T08:25:52Z","id":1356532,"component":"Autocomplete","creation_time":"2017-04-14T09:29:21Z","severity":"S3"},{"summary":"Rewrite AppConstants.jsm in 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