After uninstalling an extension that uses a floating panel, you get an annoying message about a file not being found, saying "the floater will not be shown".
This isn't a fault with the extension. It's caused by Dreamweaver creating an entry for the floating panel in your workspace file, and not removing it. The fix is usually very easy: just reset the workspace. But occasionally you need to edit one or more workspace files.
Thanks as ever David