Clues are always useful.

For this newsgroup - alt.comp.hardware.amd.thunderbird - there's the
term "hardware" in there, which suggests the actual physical pieces of
stuff that computers are made of. Then there's "amd", and there is a
company named AMD that makes computer hardware. Next, "thunderbird" is a
brand of cheap wine, so this can't be the right newsgroup to find your
answer.

Therefore, try
news://news.mozilla.org/mozilla.support.thunderbird