He got on just fine with the fans til his post backing the IDF pissed off a few, and he removed it. The majority of fans backed him and I’m sure he got a standing ovation on his last, tearful, appearance.
Not seen his post after the hamas attack but I’m sure, and I’m sure you also know, that it also pissed off some fans.
So to answer your question, to the best of my knowledge, he was never abused when he played for Celtic.