Forge Version 34.1.25
Crashlog here

Steps to reproduce:
Open inventory with Quark Oddities backpack equipped. Click and drag to fill workbench.

That was fixed by df85492
If that fix is no longer sufficient, quark will need to do something on their end, as if I can't catch their container on opening, they need to either not use PlayerContainer, or override PlayerContainer#onCraftMatrixChanged to bypass the coremod hook that I have in place.

Ah apologies, I didn't see the already closed issue.

I can confirm that with FastWorkbench 4.4.0, the issue is still happening. Hopefully quark can fix it on their end.