the b stands for bi, right? well bi is a latin prefix meaning 2 or both, eg if someone is bilingual they are fluent in 2 languages. bisexual means they are attracted to both of the sexes. so even if the b in lgtb doesn't stand for bi, then we apologize, because this is what they meant when the meme was posted.
also plz dont block me just because i made a valid point, i have had that happen before lol🤣
i also want to point out im not trying to be rude, just informative