Mozilla Releases Firefox 91 with Windows SSO Support

Mozilla has released Firefox 91 and one of the key new features is single sign-on support for consumer and commercial Microsoft accounts.

“Firefox version 91.0 [was] first offered to Release channel users on August 10, 2021,” the Firefox 91 release notes explain. “We’d like to extend a special thank you to the 210 volunteers who helped resolve more than 1,200 bugs in the Firefox 91 release.”

New features in Firefox 91 include:

Single sign-on support for Microsoft consumer, work, and education accounts. This feature allows Windows users to passthrough their Windows sign-in credentials to websites, just as they do with Microsoft Edge. You have to enable this feature first however, by navigating to Firefox settings > Privacy & Security and selecting the option “Allow Windows single sign-on for Microsoft [consumer], work, and school accounts” under Logins and Passwords. If you’re a Firefox user, you will want to do so.

Total Cookie Protection improvements. Firefox’s Total Cookie Protection functionality has been updated with “a more comprehensive logic for clearing cookies that prevents hidden data leaks and makes it easy for users to understand which websites are storing local information.”

Simplified printing makes a comeback. Firefox once again offers a “simplify page” option for printing. You can enable it in the Print panel by selecting More settings > Simplified.

HTTPS-First. Firefox offers an optional HTTPS-only mode, but with Firefox 91, the browser is adding a HTTPS-First policy in which Private Browsing windows will attempt to make all connections to websites secure (HTTPS) by default. It will fall back to insecure connections (HTTP) only when websites do not support it.

But wait, there’s more. Firefox 91 also adds support for the Scots (sco) locale, automatic High Contrast Mode when “Increase Contrast” is selected on macOS, and a few other small changes and fixes.

You can (and should) get Firefox from the Mozilla website.