If you set your jump key to Numpad Enter, when you enter a command in the chat you will jump. This is different from what happened in previous versions.
Steps to reproduce:
Create a Cheat-Enabled world
Set your jump to NumPadEnter in controls
Enter any command in the chat (/give @a minecraft:glass for example)
Expected Result: Command is executed and no jumping occurs. This is consistant with previous versions.
Actual Result: Command is executed & the player jumps.
Dupe of MC-89142