Fred J. McCall wrote

Probably right. I never paid attention to what was on it, but I could
swear that at least one F-117 squadron has the triangular patches.

http://www.thebattlezone.com/airforce/f-117.html
http://www.av8rstuff.com/f117pg1.html
http://www.av8rstuff.com/f117pg2.html
http://www.pinex.ch/patches/usaf/f117.htm

Etc. I spotted one that was really triangular and a couple that
were tending toward triangularity.