Bug, Seedbag, Shift moving, minor.

[mvgulik]

After opening and closing a seedbag*, while a other external container is open, the shift-moving items between the player-inventory and other external container is not restored.
* can be located in player inventory or the other container thats open. It don't matter which.

Minor.

Closing and re-opening the other container will restore things to normal.

[Darkren]

...This goes for everything that can be shift-clicked to move items. Including keyrings, and your equipment screen.

[Granger]

Also happens when you open a container, then open+close your equipment window.

Shift-Click/Wheel transfer is always between last opened container and your inventory.