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.Did the new firefox break the Brotli encoding?