Comment 4 for bug 113255

This error message indicates running in an unusual high-precision
display mode with 10-bits for the Red and Blue channels and 12 bits
for the Green channel. (Compared to the normal 24-bit 8,8,8)

This display mode will be slower than a normal mode, and almost all
applications on a desktop will not take advantage of it, because the
images and graphics they display only have 8 bits per channel to
start with.

Unless you are running specialized medical imaging or photography
applications that you know take advantage of such a display mode,
you probably just want to reconfigure your display to a more normal
mode for better compatibility and performance.

If you are running such applications, you'll still have to reconfigure
your display to run cairo-based applications for the moment, but it's
certainly on the list of things we'd like to fix. For the forseeable
future such a fix would just use 8 bits of every channel - that
would still be useful if cairo is only used in the user interface or
in a desktop component.

(Quick synopsis of the above: if you are offered a choice between
"32 bit color" and "24 bit color" when configuring your display, pick
"24 bit color" unless you know exactly why want 32 bit color :-)