When a fresh 3.1 site first selects to use the More 3.1 theme, the grey background image doesn't appear to kick in/display, even though I purged the cache a number of times (and tested on at least three 3.1 sites). The More settings page had the standard grey background image in the file picker, however, the default value for theme_more | backgroundimage is set to empty, so perhaps this is causing the theme processing to ignore this image initially? Once I update the background image within the file picker, save the settings and purge the cache, grey background is now displaying as expected.
Steps to reproduce
Install new 3.1 site
Switch to More theme and purge cache, and see if grey background image is viewable.
If it is, please ignore this issue!
If this is reproducible, it's not urgent, but is potentially confusing.