Minecraft: 1.12.2
Forge: 14.23.5.2854
Trophy Slot: 5.0.0
Description:

1. Have less than 9 starting slots in the hotbar
2. Open a chest
3. Shift-click on any item in the chest

The clicked item will be moved to the first and the last available slot in the hotbar. The righmost copy is phantom, and disappears when clicked/used.

You don't seem to update the 1.12.2 branch anymore, but I'd love this bug to be fixed. I made a modpack with 2 slots only based on your mod and this hinders the gameplay quite a lot.

Thank you!