Error -> https://gist.github.com/DPxKnightxZero/4d51845faf110ee8ddc5

Server-side log output caused by a "fake" item trying to use client-side stuff. On 1.7.10, this does not cause an issue to my knowledge (correct me if I'm wrong), just the log output. This was fixed on 1.8.x because it did crash.

Not worth fixing just to remove log output. I hope I don't sound rude, that's not my intention.

Its console spamming that is the issue which drops FPS to almost nothing.

This issue is so old I don't even remember what the problem was. If you are having problems with a recent version, please make a new issue.