Resizing the game window resets the checkbox value in the multiplayer warning screen

How to reproduce it:

1. If you already checked in "Do not show this screen again" you need to go to /.minecraft/options.txt and change skipMultiplayerWarning to false
2. Go to the main Minecraft screen
3. Click on multiplayer, the following image should appear
   
4. Click the checkbox (to make it true)
5. Resize minecraft window (f11 for example)
6. The checkbox has been reset to false