Firefox Beta and Developer Edition
Release Notes

Display preview image and favicon in the New Bookmark dialog

Added a Clear Site Data and Cookies button to the identity popup located next to the address bar so as to provide a quick and easy process to delete local data for the visited website

Three-pane Inspector in Developer Tools separates the rules into its own panel

New tab page sections such as top sites, highlights, and Pocket can be adjusted to include 1 to 4 rows in the Preferences

Added Canadian English (en-CA) locale

Users who disconnect Firefox for desktop from Sync are now offered the option to wipe their personal data from that device (such as bookmarks, passwords, history, cookies, and site data)

Added a button to the hamburger menu to toggle Tracking Protection on and off

The description field for bookmarks has been removed. Users who manually changed the field can export old descriptions via html or json. Stored descriptions will be removed in a future release.

The release version of Firefox 62 will be sandboxing AutoConfig to the documented API. You can test this in Firefox Beta by setting the preference general.config.sandbox_enabled to true. If you need to continue use more complex AutoConfig scripts, you will need to use Firefox Extended Support Release (ESR).

Changes affecting developers

JavaScript library for interactive editing of CSS Shapes values in the browser, with functional values like polygon(), circle() and ellipse()

CSS Variable Fonts (OpenType Font Variations) enable a single font file to behave like multiple fonts