Summary: TTYs are only available for seat0, so when starting a framebuffer kwin on seat1, it never draws, because drawing is always suspended, because it is being treated as not active
Test Plan: The framebuffer backend draws on seat1, and /dev/fb1 and when I switch back to my Weston greeter, (when it's also using the frame buffer,) it doesn't try to draw on top of it.
Reviewers: #kwin, graesslin
Reviewed By: #kwin, graesslin
Subscribers: davidedmundson, rkflx, graesslin, kwin, #kwin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D9574