Trying to open inventory crashes game

I opened a world I had been using previously in the new 18w07b snapshot and everything was working fine - I spawned the new mobs a few times, placed and broke some of the new blocks, threw the trident around, etc. After about 20 minutes or so, I tried to open my inventory again and it crashed the game. Now, hitting the inventory key crashes the game every time. I've tried changing the key and it's still the same.