tags 19999 patch
> Check "Select more than one theme at a time"
> Check "leuven"
> Check "wombat"
> Click "Save Theme Settings"
> Open custom.el
> Only one of the themes is enabled.
I'm able to reproduce this on the release branch.
enable-theme, which is called while setting custom-enabled-themes,
destructively modifies custom-enabled-themes, thus affecting what will
be stored in the 'saved-value property of custom-enabled-themes when
saving it with custom-theme-save.
One possible fix is to make the updating of custom-enabled-themes in
enable-theme side-effect free, as the attached patch does.