Steps to Reproduce the Crash

1. Open an inventory (with JEIs item grid visible)
2. Make the Minecraft window narrower
3. Observe a crash

By default the window has to become very narrow for the crash to happen, but if the vanilla recipe book is also visible it happens at something like 75% of the default window width (this has actually happened in practice).

Mod Pack URL (Optional)

No response

Mod Pack Version (Optional)

No response

Extra Notes (Optional)

Tested on commit 1a1db97 (latest at the time of opening this issue)

CC @DeadlySwede, this was originally reported by them on the IE testing server.

Crash Report

https://gist.github.com/malte0811/23048141d51ce6436c0f82c42889aeeb

Thanks for the report!
This is fixed in the next version, which should be available shortly.