Ending sentences with a preposition was another. Still drives me crazy to see those from associates. Also the misuse of then/than, their/they’re, it’s/its, could care less (I guess you could), feel badly (Really? Don’t your hands works properly?) and the mispronounciation of asterisk. All that stuff was hammered home.
I like to think most of those occur on FR
as a result of not proof reading. Then again....
“Ending sentences with a preposition was another.”
That is something up with which we should not put.