WM features

["kettani lalla fatima zahra" <kettania gmail com>]

Hi all,

i have a question about window manager's features. Is there any WM that can force an application specific window to behave as a system modal window?

I know for example that mwm offers XmNmwmInputMode resource that can be used by an application to set a system modal window, but i am interested by a customisation that could be done through WM without being invoked by the application it self.

And for screensavers, is there a WM that can allow a program to pop up over a screen saver?

If anyone know any WM that can do this please mention it, and if it doesn't exist could anyone explain to me why it is done this way?

Cheers