What are we working on?  We have long been excited to improve the existing Firefox sidebar and strengthen productivity use cases in the browser. We are laying the groundwork for these improvements, and you may have seen early work-in-progress in our test builds and in Nightly behind preferences (Firefox Nightly with vertical tabs and Firefox is experimenting with a sidebar in Nightly). What to expect next? In the near future, we will be landing foundational sidebar features in Nightly to ensure parity with the existing sidebar and make the new experience more useful and easy to use. Many ..read more

Highlights Irene has just landed a patch supporting custom color themes! You can flip the pref ​​reader.colors_menu.enabled to preview this feature in Nightly. Bug 1876432 – Add support for custom themes as its own menu in Reader View Niklas added RTL support for the new screenshots UI component (currently enabled by default in Nightly) Shout-out to Paul Bone who landed some changes to mozjemalloc, reducing the number of calls to VirtualAlloc. This change caused various improvements (3.5% – 5%) to both Speedometer 2 and Speedometer 3 subtests, with no measurable regression in memory usag ..read more

Highlights The new Screenshots component (which replaces the Screenshots built-in extension) is now enabled by default on Nightly (bug 1789727)! This improves upon the extension version of the feature in a number of ways: You can capture screenshots of about: pages and other pages that extensions cannot normally manipulate Improved performance! Greatly improved keyboard and visual accessibility You can ensure it’s on by default by checking if screenshots.browser.component.enabled is set to true in about:config Found issues with the new component? File them here! You can access the Scr ..read more

Highlights Alex added added a new option to log frame return to the nascent JS Tracer feature (bug) This can be really useful paired with the “Log function arguments and returned values”. See the example below, tracing a Redux reducer on about:home The JS Tracer is a tool that the DevTools team is developing to log JavaScript execution at runtime. This can be very helpful when debugging or exploring a new JavaScript codebase! Set devtools.debugger.features.javascript-tracing to true to enable the JS Tracer feature and try it out! Nicolas fixed a performance issue in the Inspector when ..read more

Highlights Mozilla Monitor Plus has been launched! This is a new subscription product (available only in the US for now) that will search for and scrub your personal information from data brokers. Mozilla Monitor Plus lets you take back control over your personal information. The new clear history dialog has been enabled by default at Nightly! The dialog now has a more modern look, consolidated clearing options, and shows the amount of data you clear based on time range. Additionally, all the entry points for clearing data have been unified to point to the same dialog. Congratulations ..read more

Highlights Tab Previews! Congratulations to DJ for getting these landed. Currently disabled by default, but you can test them by setting `browser.tabs.cardPreview.enabled` to true sfoster landed a patch that improves the performance of restoring many tabs all at once, especially on older machines Here’s a great blog post from the Localization team on how they’re working to advance Mozilla’s mission through localization standards Irene fixed a bunch of bugs on Reader Mode: disabled Slack in Reader View, made images easier on the eyes in the dark theme, and updated the formatting of readin ..read more

Highlights Sam is currently working to enabling the new Screenshots component on Nightly This is a replacement for the extension implementation. The component should have full feature parity, and have improved performance and accessibility. New keyboard accessibility has been added to the screenshots component. The selected region can now be moved/adjusted with the keyboard. Until this is on by default, you can enable it manually by setting screenshots.browser.component.enabled to true in about:config. Please file any bugs here Lee Salzman (:lsalzman) landed off-main-thread canvas for macO ..read more

Highlights sclements reports that the Information Management team is planning to roll out search and virtual lists in Firefox View for Firefox 123 (all features are in-tree but we’ll be enabling it all by default and landing a few additional fixes/enhancements in Nightly). For the impatient, or if you want to help test, you can enable this by setting browser.firefox-view.search.enabled and browser.firefox-view.virtual-list.enabled to true We think this should make it easier for some users to find where they’ve been. Dale has enabled Search Engine Rich Results in Firefox 122 Firefox wi ..read more

Highlights URL Paste Suggestions The URL Paste Suggestion feature is now enabled by default in the Nightly version of Firefox. This enhancement provides a convenient way for users to quickly visit URLs copied to the clipboard in the address bar of Firefox Desktop. When the clipboard contains a URL, and the user focuses the URL bar, an autocomplete result appears automatically. Activating the clipboard suggestion will navigate the user to the URL with 1 click. Nicolas added selector warnings to unconstrained :has() in Rules view (bug) An issue where switching tabs was slow because of ..read more

Highlights The WebExtensions team has been working with other browser vendors to make it easier for extension authors to migrate to Manifest v3 To allow extensions developers to use the same manifest.json file across multiple browser vendors, extensions with a manifest.json file including both background.service_worker and background.scripts will load successfully instead of failing at install time, a warning will be logged and background.scripts will take precedence over the currently unsupported background.service_worker – Bug 1860304 The Ubuntu Snap improvements for the browser migratio ..read more