Version 77.0a1, first offered to Nightly channel users on April 6, 2020
Firefox Nightly gets updated every day and as a consequence, the release notes for the Nightly channel are updated continuously to reflect features that have reached sufficient maturity to benefit from community feedback and bug reports.
Warning: Features listed here may or may not make a final release of Firefox.
In addition to these release notes, you can follow ongoing development on our @FirefoxNightly Twitter account as well as read our Nightly Blog.
The browser.urlbar.oneOffSearches preference has been removed. To hide one-off search buttons uncheck search engines on the about:preferences#search page
Experimental AVIF support can be enabled by turning on image.avif.enabled in about:config. Images accessed via a file:// handler will be rendered in-browser, but remote URLs require the server to be configured to return the image/avif Content-Type header. https://resources.link-u.co.jp/avif/ contains a large number of properly-served sample images.