Minor Open box of donuts in backpack is invisible/unremoveable

[warcrimes]

A similar and probably related bug can be reproduced as follows.
1. Enter locker, close it
2. Open backpack
3. Click-Drag any item, container or otherwise, from the bag to the locker ( you )
the item now occupies no slot, and its sprite moves to slot 1. Repeat to stack as many sprites as you wish

BONUS bug: you can't grab your backpack anymore.