Mozilla Firefox 140 release binaries are available today as what’s going to be the web browser project’s next Extended Support Release (ESR) version.
Firefox 140 downloads are now available and with this version comes the “Unload Tab” option when right-clicking on a browser tab. Now you can easily unload desired tabs to help reduce Firefox memory use and conserve CPU resources by unloading tabs that don’t need to be loaded at that moment.
Firefox 140 also finally supports the CSS Custom Highlighting API for styling arbitrary text ranges. With this API comes support for the pseudo-elements like ::grammar-error and ::spelling-error for for being able to customize how such errors are presented. Google Chrome has supported the API since Chrome 121 and so finally now with Firefox 140, so is Mozilla.
Firefox 140 also features more work on Vertical Tabs, support for adding custom search engines, Firefox for Android enhancements, and the Firefox Full-Page Translations feature will now prioritizing translating content near the current view.
Firefox 140 also brings support for the SVG fetchpriority attribute, support for the Cookie Store API, and other developer additions. New experimental features with Firefox 140 include the Prioritized Task Scheduling API within nightly builds and Atomics.waitAsync. More details on the Firefox 140 developer additions via developer.mozilla.org.
Firefox 140.0 ESR can be downloaded from Mozilla.org.
