You can download and install StuffPlug 3.5 (maybe older versions as well) for WLM 8.5 (maybe older versions as well) and use its tabs feature and deactivate tabs feature of Plus! for the time being. Also, someone else reported the same problem, even for Plus! Live:
Need Help With Grouped Chats. (Note that this thread was created when the new Live versions of Messenger Plus! didn't exist so solutions in here will probably not be valid for Live version)
My recommendation to you, update your graphics driver with the latest driver from the manufacturer of the card.
quote:
Originally posted by aaa3
secondly, i searched both manually and using search function ("tab black" was invalid coz of 3 char word, "tabs black" gave this topic)
Do this trick: black "tab " Note that there is space after tab and there are four characters in quotation marks 
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