Whenever I open a window in LFS Desktop it disappears after a few seconds, returns again after a few seconds, disappears again and so on.
Is this normal (refreshing ?) or am I doing something wrong ?

It shouldn't, are you doing anything between the times it appears and the times it disappears?

Thanks for your reply. However it turned out to be my fault.
I didn't notice that when the window isn't maximized, it disappears as soon as my cursor is outside the window.