Unfortuantely Xfce's compositor uses Xrender which does not support vertical synchronization. This seems to create a very constant tearing effect in vsynced OpenGL applications. Some drivers like Intel's open source driver or AMD or NVidia's binary blobs manage to force Xrender to vsync but the open source radeon driver doesn't …
Since I found the buttons on my monitor to be inconvenient, I decided to try to go for a commandline utility that could set the brightness. There are several ways this can be implemented:
I replaced the default browser in Xfce (Settings → Preferred
Applications) with a custom Python script to do some additional URL
handling. To open a link in Firefox you just have to run
firefox -remote OpenURL(<url>) and you can even use it with multiple
instances (add -P <profile>).
Using the …