I meant to add that if you use GNOME you can use `gnome-session-inhibit --inhibit suspend` to achieve this; I imagine other desktop environments have equivalents.
Caffeine uses (currently a patched version of) xdg-screensaver, which doesn't support this. If xdg-utils is improved to support this, it should be possible to add to Caffeine in some form.
I meant to add that if you use GNOME you can use `gnome- session- inhibit --inhibit suspend` to achieve this; I imagine other desktop environments have equivalents.
Caffeine uses (currently a patched version of) xdg-screensaver, which doesn't support this. If xdg-utils is improved to support this, it should be possible to add to Caffeine in some form.