The term Ubangi for offset extensions became a thing, because it supposedly looks like the lip plates used by a tribes in Africa and South America. (And by the way, the idea of a "Ubangi tribe" was made up in the 30s. There was and is no "Ubangi tribe".)
So, is it a racist term, when nobody is being born with lip extensions, meaning it's a reference to a cultural custom practiced by certain tribes, and not a racial slur?
And ok, I'll give you that it may be disrespectful to people with lip extensions. :) But I don't see the baggage or the racial aspect in it, other than the origin of the lip extension thingies being in Africa.
Maybe I'm being ignorant, and there is a term that was used in derogatory ways in the past, and I'm not aware of it. If that's the case, I don't want to -and won't- defend it. But if it's not the case, I think we could also move on without overcorrecting.
I believe Writer Duet imports PDFs. (https://www.writerduet.com). It's an excellent program, and it's free! That is, if you don't mind the script living in the cloud. In order to backup documents on your hard drive, you'd need the PRO version. Which still is pretty affordable at $45. ($35 with the student discount you'd probably qualify for)
Another program you might want to consider is John August's Highland (http://quoteunquoteapps.com/highland/). I believe it has a very reliable PDF conversion. Mac only, $30.
Good luck with your writing aspirations.