My Minecraft just zoomed in all of a sudden and I don't know how to get it back. It takes up the full screen, not even leaving room for the task bar at the bottom:
This is really annoying. I even tried restarting my computer but it didn't work.
By default, F11 (Fn + F11 on some keyboards) toggles fullscreen mode.
If that doesn't help, pause the game (by pressing Esc) and go into Options… → Controls… and check your keybinding for toggling fullscreen mode (under the "Miscellaneous" section).
Alternatively, you can go into Options… → Video Settings… and click "Fullscreen: ON" to turn it off manually.
You don't even need to use Alt+F4, you can just hit Esc and move the mouse to the top right and hit the small/big window button (not literally, though, as you will break your computer).
There is also another way to get stuck in the fullscreen, and that would be if you hit F11. In that case just close Minecraft and restart it. It should then be back to normal.
Go to %appdata%, click on the .mineraft folder, and in the search bar search for options.txt.
Upon clicking options.txt, you can find 'Fullscreen:true'. Toggle the state from 'true' to 'false', and relaunch Minecraft. You will no longer be in fullscreen mode.
If your not okay with Mincraft covering your screen fully, you can press F11 this works in most of the times, but if it does not work you can try
2)Open minecraft manually press "Esc" go to options--controls--see the key for your toggle fullscreen and use it
I found out that if you go to file then go back to the download, scroll to the time you downloaded the Minecraft launchers then click it and select repair and that will make Minecraft to reset all changes in settings and keep your data!