Firefox 90 release overview: Windows background updates, compatibility improvements
Firefox 90.0 is the latest stable version of the Firefox web browser. It will be released later today and most Firefox installations will pick up the update automatically.
All other Firefox channels are updated around the same time. Firefox Beta and Developer editions are upgraded to Firefox 91, Firefox Nightly to Firefox 92, and Firefox ESR to 78.12.
Check out the Firefox 89 release overview in case you missed it.
- Firefox 90 includes security fixes.
- Firefox 78 ESR is the last version of Firefox that supports Flash.
- FTP support is no longer available.
- On Windows, updates are applied automatically in the background even when Firefox is not running.
- New about:third-party page that highlights compatibility issues with third-party apps.
- SmartBlock improvements.
Firefox 90.0 download and update
Firefox 90 will be installed automatically on most devices, just like previous versions of Firefox have been. You may speed up the process by either downloading Firefox 90 manual and installing it, or by running a manual check for updates in Firefox by selecting Menu > Help > About Firefox.
Manual downloads are also available. The following pages list direct downloads for supported Firefox channels.
- Firefox Stable download
- Firefox Beta download
- Nightly download
- Firefox ESR download
- Firefox for Android on Google Play
New features and improvements
Background updates on Windows
Firefox on Windows may download and install updates in the background on Windows starting with version 90, even if Firefox is not running. It is designed to improve the overall updating process. Chromium browsers use similar techniques when it comes to updating.
The new feature applies to stable versions of Firefox only, not to Firefox ESR.
A policy is available to block the new updating behavior. Windows administrators may disable the task in the Task Scheduler as well to block these updates.
Check out Mozilla is working on Firefox background updates on Windows for additional information on the task and policy.
Third-party injections on Windows
Firefox's new about:third-party page lists all third-party modules that are not signed by Mozilla or Microsoft.
These may cause compatibility issues, e.g. crashes or other undesirable behavior.
Firefox displays the following information for each module:
- File version.
- Vendor information.
- Average blocking time.
- Process ID.
- Load duration.
An option to open the file location in the system's file browser is also provided.
HTTPS-Only mode exceptions management in Settings
HTTPS-Only mode is a useful feature in Firefox that allows HTTPS connections only be default. Firefox attempts to upgrade HTTP to HTTPS connections automatically, similarly to how extensions such as HTTPS Everywhere work. If that fails, Firefox will display a prompt to the user.
The mode can be bypassed then to access the HTTP version of a site.
To manage exceptions, sites that are allowed to be loaded using HTTP, go to about:preferences#privacy, scroll down on the page and activate the new "Manage Exceptions" button.
- FTP support has been removed. The attempt to load FTP links or type ftp links directly in the address bar displays a prompt to pick a handler for the protocol in Firefox 90.
- Print to PDF creates working hyperlinks in Firefox 90. Users who open the PDF documents can activate the links to open the linked resource.
- SmartBlock version 2.0 improves privacy by blocking Facebook scripts by default but loading them when they are needed, e.g. when a user selects to sign-in to Facebook.
- Open Image in New Tab loads the media in a background tab now.
- Most Firefox installations without hardware accelerated WebRender will now use software WebRender.
- Improved software WebRender performance.
- Enterprise: AutoLaunchProtocolsFromOrigins policy is now available. Defines a list of external protocols that can be used from listed origins without prompting the user.
- Enterprise: BackgroundAppUpdate policy controls the background updates feature on Windows.
- HTTP fetch metadata request headers are supported. The new feature protects against types of cross-origin attacks when implemented correctly on servers. Check out
Mozilla Security's blog post on the introduction.
- The matrix URI scheme is supported by add-ons in Firefox 90.
- The cache API can be used by extension pages and worker globals.
- Support for private fields available in DevTools.
- Ability to use client authentication certificates stored in hardware tokens or in OS storage.
Security updates / fixes
Security updates are revealed after the official release of the web browser. You find the information published here after release.
Firefox 91 will be released on July 27, 2021. It marks the start of the next Firefox ESR branch. Firefox ESR 78 will receive its last update on October 5, 2021.
Recently Reviewed Firefox extensions
- Auto Cookie Optout responds to cookie prompts automatically in Firefox
- Browse YouTube from a side panel with the Sidebar for YouTube extension for Opera and Firefox
- Distract Me Not is a website blocker extension for Firefox
- NelliTab is a highly customizable new tab extension for Firefox and Chrome
- Open Multiple URLs is an extension for Firefox and Chrome that can load several URLs in a couple of clicks
- Sage-Like is a customizable RSS feed reader extension for Firefox
- View your browsing history in a nicer interface with the Better History extension for Firefox
Recent Firefox news and tips
- Firefox Lite is dead: development has ended
- Firefox will soon support multi-page login forms
- Mozilla launches Ideas platform to improve communication with its userbase
Additional information / sources