Issue: If you walk in any direction when you toggle full screen by using F11, you'll keep walking in the same direction without pressing any buttons. You have to press the buttons of the opposite direction to stand still.
How to fix: Either open the pause menu, the inventory or a GUI.
How to replicate:
1. Press any of the WASD keys
2. Toggle full screen using F11
Duplicate of MC-1519 - If you have not , please use the search function in the future, to see if your bug has already been submitted. If you could not find the original report, please comment with the keywords you searched for.