I play CMP on my own server with 1-4 players, no modded pure vanilla. The freeze started since about 13w42a (not exactly sure) and also happening to my friend who plays on same server with me.

Basically, at random interval, game suddenly freezes with no strange behavior prior and I am forced to shut down the game manually via task manager. There is no apparent crash report since I had to shut down the game manually. Launcer console have no good hints about causes of freezing.

I've noticed game does not freeze when not using fullscreen, but instead ignores all keyboard/mouse input and leaving me to force shutdown PC (since I cannot access task manager). However my friend's client did froze no matter he was using fullscreen or not.

The file "hs_err_pid4688.log" did generate however so I've attached file.

EDIT: This confirmed to be true even if you were idle. Meaning that it's highly likely that freezing has no relation with player's action.

EDIT: We were using private resource pack in private map/server.