Hi, An xubuntu user reported that the workspace switcher panel plugin has a non-transparent background, which he finds ugly if the panel has a background image or transparent background. I don't use these options myself (the "background image" case looks sensible, but I think that a transparent background on a transparent panel will make the workspace switcher hardly usable), but maybe you'll think that's worth considering. Thanks.
This is an external widget we're embedding, I don't think we want to complicate things further with it.