Borderless? Why on earth would you want a borderless window? You can't move or minimize a borderless window!
Windowed mode with window decorations and resizing + minimizing + closing intact, please.
You are not supposed to move or resize it. it is the same size as your desktop, covering it entirely.
Borderless window mode (See WOW for another example) look exactly like full screen; the differences are in how it works. The game is more stable and less prone to crashing, the game has better compatibility with future windows versions and resolutions, and most importantly, the game works perfectly with alt tab and the windows key.
Alt tabbing is instant and does not disrupt game-play and does not risk crashing (common with outdated DX versions).
Hitting the windows key in fullscreen mode minimizes the game, changes the resolution (some times more than once) and finally a few seconds later opens the start menu. Then clicking on the game will change the resolution again, then maximize the game. Taking another few seconds... and is likely to cause a plethora of bugs.
But in a borderless window hitting the windows key simply makes the start menu pop up instantly on TOP of the game. Allowing you to either click something on it/start bar. Or or to click anywhere in the game to bring it back into focus, all instant, and all perfectly stable.
The only drawback is that vsync is more complicated to implement and is often omitted.
