I originally reported this bug here: http://newsgroup.xnview.com/viewtopic.php?f=62&t=29201
I am still experiencing this issue on my Windows 8.1
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reproduction;
1.) use my custom xnview.ini (I've email sent to Pierre)
2.) Open the XnViewMP app (xnview.exe)
3.) You should see an <Empty tab> because the setting "Open browser on startup" is disabled
4.) Now open the 'About' as a tab
5.) Now close the 'About' tab
6.) Now notice how the tab name (<Empty tab>) is missing
