Non-transparent window?

[Froggo32]

Yo
So lately I've been trying to make my own game in MV. I managed to find out how to edit windows, but there's one problem. It's transparent. I want it to not be like that since I'm going to make a retro styled game and I just cannot let it be transparent.
So, how to change dat?

 

[tale]

With Yanfly's Core Engine (YEP_CoreEngine) plugin, for category Windows- change Window Opacity to 255 to look solid.