Opacity setting disapeared

[george-e-porge]

hello, im running mint 12 KDE 64 bit, one of the features i really liked about it (actually, the reason i picked it over others) was this little button:



The problem being that underneath the "To Desktop" option there used to be an opacity selector (100%, 90%, etc). Now it is gone. I am fairly sure that when i updated my system, but am unsure how to get that functionality back aside from a reinstalling from the dvd.

Any help?

[cirrus_minor]

its under advanced/window settings