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is Unreal Engine 4 incapable of launching games in fullscreen?

https://answers.unrealengine.com/questions/346224/make-packaged-game-fullscreen-without-editing-ini.html

People keep telling me I have to edit an INI file or run a console command.

What if you have a finished game, do you expect the end user to have to enter fullscreen manually every time?

In blueprints, at your start game event add a console command “fullscreen” before the rest?

As Aquazi said, just add run console command with “fullscreen”.
Also, all graphical option such as resolution/fullscreen and etc coming to Blueprints in 4.11

If you are referring to play in editor then its the “F11” key and for complete fullscreen without start menu use “shift+F11” then press Alt+P to play in editor fullscreen, saves a lot of performance over play in new window