Height of the page content should be at least the height of the window
On pages where there is not enough info to display (login, welcome on high devices, ...) the "#main" HTML component does not go further than what it needs, meaning the two side nav columns that are gray stops before reaching the footer and that's ugly.
The "#main" HTML component should be given at least the size of the window, so navbars always go all the way down.
Be careful to check that the solution works both with and without the "accept_cookies" banner.