Fullscreen size should be improved

[Gilbertdelyon]

In NEW POST, NEW COMMENT and ADD MESSAGE editor the full screen size is fully hidding the mother page. It looks like if we have lost the site.
Buttons in menu bar are too small

In NEW CONVERSATION editor the fullscreen is smaller than the normal size, and buttons are also smaller

I would suggest a "nearly" full screen in all cases, with a small margin, so that the mother page still remains in the background, and also bigger buttons in all cases.

Please have a look to how it works in our site (5 minutes video) , thanks to additionnal CSS in a custom theme.
This video will compare the native behaviour to our custom theme behaviour.