Mozilla Firefox 121 Is Now Available for Download, Here’s What’s New

[polymath]

Mozilla published today the final build of the Firefox 121 web browser, slated for release on December 19th, 2023, so it’s time to take a closer look at the new features and improvements.

The big news for Linux users in Firefox 121 is the enablement of the Wayland compositor by default instead of XWayland. Apart from improving the graphics performance, this also brings support for touchpad and touchscreen gestures, swipe-to-nav, per-monitor DPI settings, and other goodies.

However, Mozilla notes the fact that due to some Wayland protocol limitations, Picture-in-Picture windows will require an extra user interaction, such as a right-click on the window. This can be workaround on GNOME by using the PiP on top extension, and on KDE Plasma by using this tweak.

Also new in Firefox 121 is support for force-underlining links in websites, which may be useful for people with achromatopsia, as well as a new floating button to simplify the deleting of drawings, text, and images added in PDF documents.

For web developers, Mozilla Firefox 121 brings support for the :has() selector by default to allow you to match elements that have at least one element matching its relative selector, adds support for lazy loading iframes, and adds support for text-wrap: balance to improve the appearance of short multi-line text blocks.

In addition, it adds support for hanging and each-line keywords to the CSS text-indent property, as well as support for “tail call elimination” in the WebAssembly language to improve support for functional languages. Also, the Firefox Debugger received a new option to disable the debugger; keyword on the current page.

I also noticed the fact that Firefox 121 also shows the Mozilla VPN under Settings > More from Mozilla, so you can more easily access Mozilla’s VPN (Virtual Private Network) service. Previous versions, such as Firefox 120, showed only Firefox Mobile and Firefox Relay options there.

As mentioned before, Mozilla plans to officially announce the Firefox 121 release tomorrow, December 19th, 2023, when it will be available as an OTA (Over-the-Air) update for macOS and Windows users. Since that’s not the case for Linux users, you can download the binaries right now from _Mozilla’s download server