When a window gets the demands attention hint (_NET_WM_STATE_DEMANDS_ATTENTION) or the urgency flag, the pager flashes the window’s entry on the taskbar. Other pagers such as AWN may bounce the window’s icon in their dock. However, the window itself doesn’t change at all. To remedy, this, GNOME bug 120406 suggests that the frame, or the titlebar, of a window which demands attention should flash as well.
One problem with this is that a window which demands attention necessarily isn’t on top, so is likely to be at least partly obscured. On the other hand, someone suggests that the existing visual-bell mechanism could be reused here instead.
Photo © juliebee, cc-by-nc-nd.
What about using opacity when the compositor is on to draw attention to the window? For example change the opacity of the window shadow back and forth for a while to give a slight hint, or the window decoration opacity…
“One problem with this is that a window which demands attention necessarily isn’t on top,”
In fact, if the application demanding the attention *is* on top, then nothing should be flashing or bouncing at all– that’s certainly how OS X and Windows work. There’s no need to draw my attention to the front-most application, I’ll already be able to see that it wants something. If GNOME doesn’t work like that, I’d consider it to be a bug…
I think perhaps you misread the post as saying “isn’t necessarily on top”.