Really weird autocorrect issue im experiencing with the firefox app? (opens in new tab)

So I dont know which update this followed, it's been happening for some time now and specifically with firefox\. When i typo a word and go back to change a letter with predictive text on, it will straight up insert the whole word and put a space after the word before the last letter of the word i was already trying to fix\. For example, if i typoed insane as \"isnane\" and went to correct that, it would spit out \"ininsaneane e\" or something like that\. I cant use predictive text at all whic...