The latest Firefox version broke ChatGPT website

by vannion 1/15/2026, 11:48 PMwith 7 comments

by kmarcon 1/16/2026, 1:53 PM

Unfortunate; This morning my firefox profile didn't start up, draws the empty window, and spins the CPU. I started my workday with downgrading FF and restoring my previous profile from a backup.

Now this.

FWIF, for this particular problem, the workaround from the linked reddit post works:

Edit 3: This workaround seems to fix it:

    type about:config in the URL bar
    search for network.http.accept-encoding.secure
    replace gzip, deflate, br, zstd with gzip, deflate, zstd
Alternatively, set network.http.dictionaries.enable to false.

by 6thbiton 1/16/2026, 12:20 AM

Some request errors relate to "NS_INVALID_CONTENT_ENCODING". In such requests that is set to Content-Encoding: br

Did the new firefox break the Brotli encoding?

by vannion 1/16/2026, 12:06 AM

https://bugzilla.mozilla.org/show_bug.cgi?id=2010712

https://github.com/webcompat/web-bugs/issues/201270

by OptionXon 1/16/2026, 2:56 PM

In about:config set network.http.dictionaries.enable to false to fix it.

source: https://github.com/webcompat/web-bugs/issues/201270

by QuiCasseRienon 1/16/2026, 1:28 PM

Two days and still no update for users, it's a shame at that level (of product scale) !

by lobito25on 1/16/2026, 2:07 AM

I didn't update FF and have the same problem. I think it was the other way around.

by daveoc64on 1/16/2026, 1:07 AM

I'm glad I'm not the only one with this problem!