Random crashing

Build: 418100
Summary:
Game will just randomly crash now.
Impact:
Have to keep reloading Minecraft
Repro Steps:
1.The game was loaded for some time and I switched between a few worlds, but all I did was search for webs in the gui. This is obviously not consistent. The first time it happened I was searching for dye.
2.watch it crash
Observed Results: Crashed
Expected Results: not crashed
Screenshots/Videos attached: yes