Slightly different to 1861534 I think.
On installing 126.96.36.199 (without Uninstalling 188.8.131.52) The app repeatedly hung on startup whilst trying to update feeds (curiously mostly on a sourceforge forum page within the RSSBandit feeds).
I uninstalled 184.108.40.206 and reinstalled (trying another few times without success - would get slightly different levels of activity on startup before hanging).
After then looking at trace logs and using Process Monitor to check what was going on (nothing much), I found a few exceptions for missing xml files (which seemed to be ignored anyway). I tried adding empty files (trace log then showed invalid xml - as expected but no change to behaviour). Then looked at openbrowsertabs.xml and removed the two items that were there (two pages I was looking at before upgrading).
The app then started up fine - so I'm guessing there's an version incompatibility somewhere possibly schema-wise in that file?
Trace log attached.