Summary:
The game switches back to fullscreen mode when restarting the game if you use the title bar to switch to windowed mode. This issue does not occur when using the F11 key.

Steps to Reproduce:

1. Put Minecraft in fullscreen mode
2. Move the cursor to the top of the screen to bring up the title bar
3. Click on the button between the minimize and close buttons
4. Restart the game

Observed Results:
The game switches back to fullscreen mode.

Expected Results:
The game remains in windowed mode.