Well, I’m using Fritzing 0.9.4 under Mac OS Catalina 10.15.4 with very few problems - mostly of my own making!
i.e managed to duplicate a part but still had the same id so an error occurred - easily fixed !
Also trying to add a strip board for prototyping with more rows and/or columns than the standard set size seem to provoke a memory attack of the rainbow spinning ball and it slows to a snails pace.
So what actually happens on your machine after a double click - something must happen albeit that it launches and quits immediately with no warning. Almost sounds like a corrupt support file - plist or similar. Maybe a complete deinstall using an app such as ‘ApplCleaner’ (free of course) to make sure all remnants of the old version are removed and then a clean install again might help!
PLEASE - make a backup of parts database and your own first!