These Weeks in Firefox: Issue 108

Highlights

• Reminder: FOSDEM 2022 is happening the week after (February 5 & 6), and is free to (virtually) attend! Lots of great talks from Mozilla and others.
• Infrastructure for site-specific video wrapper scripts are now available for Nightly!
  • This will allow us to create scripts to declare site-specific behavior for Picture-in-Picture. This gives us the foundation to support full controls, subtitles / captions and more on sites like YouTube, Netflix, Amazon, and Prime Video.
  • As a proof-of-concept, our first wrapper for YouTube lets the Nightly-enabled mute control properly update the mute state in the originating video player.
• Our latest cohort of MSU students have started working on Reader Mode and the readability repo so many new changes will be landing soon!
• A new and improved Downloads experience is riding to release in 97. There’s a SUMO page that lists some of the bigger changes.
• Many new changes added to Developer Tools

• • Greg Tatum added UI in the Browser Toolbox to toggle Fluent pseudolocalization bidi / accented (bug)

DevTools UI toggles for Fluent pseudolocalization: “accented” and “bidi”.

• • The compatibility panel will ride the train after being enabled on Nightly/DevEdition for a while. It provides useful information on CSS properties, using MDN compatibility data (bug)

The DevTools compatibility panel will ride the trains!

• • Auto-open devtools for tabs opened via window.open (behind devtools.popups.debug) (bug). On a page where you already have DevTools opened, if a new tab is created via window.open, the toolbox will automatically move to the new tab, with the new document selected in both the iframe picker and the context selector

We can now see and navigate across new tabs in DevTools!

• • Event listeners for a given node can now be disabled from the Inspector Event Tooltip, in the markup view (bug). Also, The “event” badge style is updated when at least one event is disabled to remind the user that something was changed (bug)

Event listeners can now be disabled from the Inspector Event Tooltip in Browser Toolbox.

• • “Ignore line” context menu entry added in the debugger editor gutter when devtools.debugger.features.blackbox-lines is true (bug). Also, there is better “Ignore source” icon and editor background colors for ignored lines (bug)

A new context menu entry in the DevTools debugger has been added for ignoring specific lines of code!

Friends of the Firefox team

Introductions/Shout-Outs

• Welcome to sclements!

Resolved bugs (excluding employees)

Volunteers that fixed more than one bug

• Claudia Batista [:claubatista]
• Mathew Hodson
• Shane Hughes [:aminomancer]
  • Really great work in Downloads and Themes!

New contributors (🌟 = first patch)

• 🌟 kabakert fixed open download doesn’t show negative time anymore
• Rashelle fixed Picture-in-Picture window has no window icon
• Sai Hemanth fixed error when clicking on “scroll” badge when element causing overflow has pseudo element
• Tawah Peggy removed lodash from Pairs|toPairs usage

Project Updates

Addon Manager & about:addons

• Mark Striemer fixed an accessibility issue related to screen readers behavior on the about:addons page “More Options” menu associated with each add-on card – Bug 1750799

WebExtensions Framework

• In Firefox 98, cached images loaded from a moz-extension url are explicitly cleared between addon updates (and temporary addon reloads), instead of being wrongly loaded from the stale cached data – Bug 1746841

WebExtension APIs

• Richa Sharma contributed a new “contextual identities” (also known as “containers”)  related additions to the Extension APIs: the userScripts API now allows to register user scripts that match only documents loaded in a specified set of containers (given an array of the userContextId to match) – Bug 1738567
• As part of the ongoing ManifestVersion 3 work, William Durand landed in Firefox 98 more bits of the new “browser.scripting” API:
  • scripting.insertCSS – Bug 1736579
  • scripting.removeCSS – Bug 1736580
  • Support array of files in scripting.executeScript – Bug 1736576
  • Support target.allFrames in scripting.executeScript – Bug 1736574
  • Allow scripting.executeScript to run the content script in about:blank pages and sandboxes frames – Bug 1739643
• Starting from Firefox 98, only webRequestBlocking listeners will make an addon to start sooner during the browser startup – Bug 1749871

Developer Tools

• Oriol fixed the rendering of Arrays with RTL characters (bug)

• Lodash was removed from the tree after replacing all its callsites in the debugger (bug)

Reader Mode (MSU Capstone project)

• niklas and mtigley hosted a hack weekend with MSU students from January 15 – 16 to get them up to speed with Firefox front-end development and their first bugs
• Students are hacking on both the Reader Mode view in Firefox and the mozilla/readability repo itself!
• Tyler is working on an issue where Reader mode displays “Failed to load article from page” when reloading this page
• Steve is fixing an issue with drag/drop from the location bar / identity icon when in Reader mode doesn’t provide the original URL
• Emily is adding a keyboard shortcut where the user can toggle narrate mode!
  • She’s also started making it so Readability.js exposes the original document’s “lang” attribute, which will help fix bug 1474565
• Jintao is created a pull request to make it so isProbablyReaderable works for article tags too
  • Adding bottom margin to images with figcaption in Reader Mode: Block images sometimes lack bottom margin
• Chad is working on making it so the pocket button acts like a toggle for the pocket panel
• Noel worked on an issue: Video element exposes unnamed graphic and button
  • She’s now working on providing an option make Reader Mode fullscreen 

Lint, Docs and Workflow

• import-globals-from now supports absolute directories.
  • e.g. /* import-globals-from /toolkit/content/globalOverlay.js */

PDFs & Printing

• jwatt removed the old print UI
  • Bug 1702501 – Remove print.tab_modal.enabled pref and old frontend print preview code
• jwatt added a pref to show the Page Setup menu
  • Bug 1745465 – Add a pref to enable the Page Setup menu

Picture-in-Picture

• Ania recently opened a meta bug for tracking support for captions/subtitles in the PiP window

Performance

• Thanks to mixedpuppy for making it possible to start Firefox faster when there aren’t any webRequestBlocking add-ons installed!
• Thanks to barret for continuing to burn down our old main-thread disk access mechanisms. FileUtils.getFile and FileUtils.getDir are heading into the bin!
  • Please use IOUtils and PathUtils when you can.

Privacy/Security

• Private browsing windows will be themed dark for compatible themes
  • The feature is still WIP and can be enabled via the browser.theme.dark-private-windows pref
  • Enabled for the default theme in light mode and other light themes which expose darkTheme data, such as Alpenglow.
• Hannah is working on deprecating the cookie lifetime policy.
  • Currently controlled by a checkbox in about:preferences#privacy
    “Delete cookies and site data when Nightly is closed”
  • It will be replaced by the sanitize-on-shutdown mechanism
  • We will keep supporting exempting sites from getting cleared, but we’re looking to remove support for adding sites *to be cleared* explicitly

Search and Navigation

• Firefox Suggest opt-in modal redesign:
  • Drew (adw) made the modal not be shown on top of about:welcome
  • Daisuke added a tooltip to the modal’s close button
  • Drew fixed some accessibility problems
  • Drew made Firefox Suggest toggles/checkboxes in about:preferences play nice with session restore
• Mandy (mcheang) added locale and region properties to the search metadata object
• Drew fixed a bug that prevents search mode from being exited via ESC in new windows
• Daisuke fixed a problem with Japanese IME (Input Method Editor) in the search bar

Screenshots

• Niklas got a fix in for Bug 1751060 – Screenshots extension panel SVGs lost blue background color.