Played half a dozen games on 1.11.2 today and finally managed to crash. I can confirm that it's the same crash as with 1.12.2 and relates to, at least sheep and maybe also pigmen. It is something the dev team is aware of, unfortunately resolving it is a little bit more involved than we would like. At this point, 1.10.2 does seem like the best version to play on for a crash free TD experience. Getting this fixed is something that will have to be done as part of a much larger update, we will get to it, it'll just take some time.