Microsoft Teams throwing 'browser unsupported' error on Firefox, issue acknowledged (workaround inside)

Firefox is one of the first and most well-known open-source web browsers created by the Mozilla Foundation.

The performance of video playback and the quality of video scaling were both improved with the release of version 110.0 on February 14, 2023. Also, the fullscreen notification not shown in Firefox Focus has been fixed.

Yet it appears that there is a problem with Microsoft Teams on the Firefox web browser, since some users are unable to access it (1,2,3).

Firefox is a supported browser, as noted on the official Microsoft website where it was under development for a while, even if there hasn’t been an official announcement yet.

Nevertheless, as of late, some Firefox users are encountering an error stating that their ‘browser unsupported’ each time they attempt to enter Microsoft Teams on teams.live.com.

In the Business/Enterprise (teams.microsoft.com) domain, this is not the case as everything appears to function normally.

@Microsoft couldn’t get any worse after they made @firefox not compatible to run microsoft teams web they are forcing users to use either chrome or edge
Source

Fortunately, a Mozilla engineer confirmed that it’s a known issue and Microsoft is working on it. However, no ETA for a fix was shared.

There is a potential workaround, though, in which you need to utilize a ‘user agent switcher‘ to appear to be using a browser other than Firefox.

try using this extension to spoof your user agent
Source

A few users report that it works with Firefox v110.0, therefore you might try updating to that version. Additionally, disable any ad blockers that may be causing this problem.

Works fine for me. I’m on Firefox 110.0. Maybe you have an ad blocker or something like that interfering?
Source

If the aforementioned workaround helped fix the issue, do let us know in the comments down below.

Also, we will be updating this space once the problem is resolved so stay tuned for more information.

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