Weird, weird weird Windows 10 edition bug.

I'll say it as concisely as possible:

• Turning on Fullscreen Mode in Win10 edition causes the game to disconnect from servers within literally 5 seconds of minimizing the game. It's really irritating, and I only made the connection between the two today.
• Turning Fullscreen Mode OFF immediately solved the problem.

This bug doesn't affect singleplayer as far as I can tell. I haven't tested for local multiplayer.