These Weeks in Firefox: Issue 89

Highlights

• Visualization of the CPU utilization is landing soon! Example profile (currently deploy preview) You can toggle the new/old visualization from the “graph type” radio button on the top left corner
• Thanks to emilio, “Break On Attribute Modifications” in the DevTools Inspector now works for style attribute modifications or Shadow DOM
• Non-native theming for form controls in content has been enabled on Nightly. This is needed for content process sandboxing and will help us ship Fission.
  • This bug tracks letting it ride the trains
• Improvements to our Screenshots feature and Downloads Panel were accepted as Outreachy projects this summer!
  • Apply here! We’d love to work with you.

Friends of the Firefox team

For contributions made from February 23, 2021 to March 9, 2021, inclusive.

Introductions/Shout-Outs

Resolved bugs (excluding employees)

Fixed more than one bug

• Itiel
• Mattias de los Rios Rogers [:delosrogers]
• Michelle Goossens
• Oliver Pope
• Patrick Storz
• Andrei Petcu
• RAHUL SAWRA[:rsawra]
• Sebastian Zartner [:sebo]
• Tim Nguyen :ntim
• Tom Schuster [:evilpie]
• Tom Tung [:tt, :ttung]

New contributors (🌟 = first patch)

• 🌟 Yogitab2798 added event listener breakpoints for focusin/focusout.
• Oliver Pope fixed a JavaScript console error thrown by Picture-in-Picture, and moved PiP overrides from the webcompat add-on into its own system addon.

• 🌟 Mattias de los Rios Rogers removed defer usage in devtools/shared/security/tests/xpcshell/head_dbg.js and fixed capitalization of DevtoolsStartup in DevToolsShim.jsm.

• 🌟 Ankit Jain fixed the label on the “Edit” option for SVG, XML, and MathML.

• 🌟Rahul Sawra downgraded “Already started legacy listener” error messages to warnings and ensure Symbol descriptions were quoted in DevTools.

Project Updates

Add-ons / Web Extensions

WebExtensions Framework

• Fixed a bug in MatchGlob that was triggering a browser main process hang when an extension was passing to browser.tabs.query a URL with many redundant wildcards characters – Bug 1570868
• Investigated and fixed a tabs API regression introduced in Firefox 86 – Bug 1694699 (the underlying issue was actually an old typo on the tabbrowser side, fixed in Bug 1498432)

WebExtension APIs

• Added “url” support in the optional filtering option supported by the browser.tabs.onUpdated API event – Bug 1680279

Developer Tools

• Browser toolbox now starts even if there are pending updates (bug, contributed by :nalexander)
• Inactive CSS support improved – new warning displayed when grid-template* is used on non-grid containers (bug)
• The team is focusing on fixing remaining Fission M7 blockers

Installer & Updater

• 1120863 – nalexander fixed a longstanding issue with running the Browser Toolbox when an update is pending.
• nalexander’s work on the background update task continues, landed 1695797 (only process updates if we’re the only instance running) and 1695754 (background task docs).
• 1691486 – bytesized extended per-installation preferences beyond just app.update.auto.
• 1690064 – bytesized made uninstalling and reinstalling more consistently clear per-installation prefs and updates.
• 1685213 – agashlin landed shortcut and taskbar pinning telemetry

Messaging System

• Turned off most CFR (Contextual Feature Recommender) messages for 89+ wanting to minimize interruptions
• Cleaned up unused welcome flow to simplify platform-customized defaults
• Fixed “Save Theme” wording and negative outline clipping with RTL+scale(-1)

Password Manager

• Thanks again to Andrei Petcu for ongoing work on Import logins from CSV
  • Detailed import report landed,
  • Username no longer a required field/column
  • Just one telemetry bug open before this is ready to pref on and ride to release
• We have exciting work-in-progress to bring “related realms” to login autocomplete. Think: apple.com / icloud.com
• As well as ongoing work in the never-ending arms race to improve login capture. We want to offer to save a password, but when? When is a login form submitted if there is no <form>, and no submit button?

PDFs & Printing

• Tom Schuster – Bug 1694844 – Fixed a bug where the print dialog wouldn’t open on linux if CUPS wasn’t installed

Performance

• masterwayz removed OSFile.jsm usage from XPIProvider
• emalysz removed the slow startup warning notification bar
• dthayer updated the slow script notification bar so that it only shows up if the user tries interacting with a hung tab. The threshold was also increased to 10 seconds, and information about which tab is hanging was also added to the infobar.
• florian landed some improvements to about:processes, and got a few unnamed threads identified and named
• florian made it so that bulk closing many tabs should be faster in some situations
• Gijs made it so that we don’t try to run permitUnload for tabs that we know are hung, which should improve tab close tabs in some situations
• mconley shipped the Pre-XUL Skeleton UI experiment. It’s currently running for a subset of our release population. Enrollment should have completed, and the users in the treatment branch should be seeing it soon.

Performance Tools

• Added nested event loop markers. Example profile: https://share.firefox.dev/3qdqZYZ
• Fix for broken JIT stacks is underway and it’s very promising so far. Prototype working on Windows x64.

Firefox Profiler has improved the appearance of the stack chart

Picture-in-Picture

• Oliver [:popeoliv] finished moving PiP site overrides from the WebCompat addon into its own addon (bug 1690076)
  • Special thanks to Rob Wu, Dennis Schubert, and Thomas Wisniewski for helping us through this
• Oliver [:popeoliv] fixed a JavaScript error where contentWindow isn’t available when calling requestIdleCallback (bug 1676569)
• Hunter [:whjones526] started a prototype patch that allows users to move the PiP toggle button to either the right or left side (bug 1550453)

Search and Navigation

• Improved architecture for removal of search engines, and working on improving fallbacks when the default is removed.
• Fixed a bug causing duplicate search suggestions – Bug 1694237

WebRTC UI

• pbz and jib have patches up that will grant a ~50s grace period for a site to reacquire a device that they’d previously been given access to, without re-prompting.