When I open a text document after saving it, “ff” is missing. It’s been removes. If I wrote the word “official”, It would show as “o icial” WTF? I’ve checked to make sure there are no find/replace commands.
What version of LibreOffice?
What operating system?
What font are you using?
Is OpenGL enabled in Options > LibreOffice > View ?
That sounds like a problem with ligatures. Does it also happen with fl and fi? Make sure that the font that you use supports ligatures when you have autocorrect settings to replace for instance ff by the ff ligature.