Hi, could you re-attach the images to a reply? https://support.mozilla.org/questions/1212380#question-reply

Oops sorry, probably was a problem when I attached it the first time.

Hmm, I don't recognize what Firefox is using there. How are you instructing Firefox to use a particular font for that character? (Whatever it is, it's not working in this case.)

Consider substituting Unicode for symbol font characters for better cross-browser and cross-operating-system compatibility:

⇨ https://www.fileformat.info/info/unicode/char/21e8/index.htm

I see. Understood then. Thank You for the advise.