I don't know if you guys intended this behavior but here goes my impression on a interface (in my opinion) issue.
If I try to scale down the Message window, geany will allow me to do so to such a extent that it will endup hiding some of the lower tabs.
For usability reasons I think it would be sensible to allow the user only to shrink the window to the size the tabs will be visible (bad Idea in my opinion) or to move the tabs to the bottom or top of the area, so they don't need so much vertical space in the screen (which I'd vote for).
As I'm only the "newcomer" I understand if this is the behavior you want, just thought I should add a couple cents :)
Cheers, Alexandre Moreira.
PS: I tried to find a way to change the position of the tabs, but could not. If this option exists please ignore the above complaint :)