Pre tags don't have background in dark themes
Expected: it should look like the preview
Actual: it doesn't have a background or it is too close to the post background color
Looks like the background color of the composer preview is different than the background color of the forum.
the background color of the composer preview is different than the background color of the forum.
Different background confirmed
@ben_lubar I understood what you meant, though. The composer preview (and the expanded reply section under posts, too) is significantly special enough that CSS that's supposed to style posts (and does style them once they're posted) sometimes doesn't apply to them there, and has to be fixed.
(I mainly just noticed that in my userscript development.)