Does RP use any sort of automatic word completion program that fills in words while typing?

I ask because lately I've been getting really strange automatic word completions while typing posts. I used to get minor ones, like it changing "there" to "their". But now I type words and get completely unrelated words. For example, I typed the word "completion" in my question title. I'm sure I hit all the correct keys. But when I reread it, it said "comment legion" instead of completion. WTF? I always thought that it was an iPad function doing these changes, but now am not sure, as I don't have this problem on other sites. Anyone else seeing this?
Edit: I just saw that in my example about how it changed the word completion in the title, it changed it again in this post to "comment lotion". Help!