When you scale up the text in Firefox with the Zoom function (Ctrl++) when the option "zoom only text" is set, then the TabStrip layout gets disturbed: additional background images get visible below the TabStrip. This can be seen on the Telerik TabStrib demo page as well.
Setting the font to a fixed size (e.g. 12px) in my project's CSS file doesn't help. Does anyone know a workaround? Thanks!