In 9e8499bb, we forced image and drawable
previews to be 8 bit integer for compatibility.
However, this affects image previews when
in higher precisions, leading to banding
and other conversion issues.
Since the color space invasion, the original
problem should have less of an impact
as GIMP now handles conversions between
profiles much better. Therefore, we will
just grab the existing format for Grayscale
and RGB images, rather than forcing a
precision change to 8 bit.
c548ca5dfd