When using a global keyboard shortcut (I use Win+F5 through Win+F8) to control a media player (I've tested JuK and DeaDBeeF), Minecraft goes from fullscreen to minimized for some reason. Every time!
Linked issues
Comments

When using a global keyboard shortcut (I use Win+F5 through Win+F8) to control a media player (I've tested JuK and DeaDBeeF), Minecraft goes from fullscreen to minimized for some reason. Every time!
Yao Mitachi
(Unassigned)
Unconfirmed
Minecraft 1.11
Retrieved
Please check if the latest development snapshot 17w43b fixes your issue.