Help! Magic Farm 2 Inventory issue

[Mizuki Ayu]

Whenever I click on an item, instead of going into my hand (floating to be put in a crafting table say) it will put 1 item from the stack onto my hotbar (or viceversa) I can't find a key to stop this and it makes the game impossible to play.

 

[ThatOneSlowking]

Either enter and exit fullscreen, or exit client. It is a bug that has existed in vanilla minecraft since 1.7-1.8 ish

 

[DREVL]

^^^