It may be that I'm silliy enough to maintian a couple of ancient addons and I'm not lua smart enough to spot the flaming obvious. After the last stealth patch that seemed to fix this problem I was still getting the error after opening the options window for "my" addons and then trying to open other in-game windows guild, friends, professions etc.
I tracked the problem down to the TOCs containing the following entries
Code:
..\..\FrameXML\Fonts.xml
..\..\FrameXML\UIDropDownMenuTemplates.xml
..\..\FrameXML\UIDropDownMenu.xml
..\..\FrameXML\UIPanelTemplates.lua
..\..\FrameXML\UIPanelTemplates.xml
Once they were deleted, problem solved.
If you find this usefull great, if you find it an excuse to point out how lame I am at coding, enjoy
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