The lack of notification was likely my fault, I tend to use the general reply button (which doesn't email notifications) unless (like this time) I think about it. With the warning I'm a Windows Fritzing user not Mac, there should be a directory (from the parts file format doc at)
called ~/.config/Fritzing on the Mac (which may be hidden because of the . in front of the .config on Unix utillities, an ls -a in a command prompt should display it). On Windows you have to specifically enable displaying hidden files to display it. This directory is the parts database which sometimes gets corrupted and your user sketches are in
/Users/username/Documents/Fritzing/parts
apparantly (I expect as with windows you need to replace username with your Mac user name). On Windows 10 (which I also don't run 
) some of the latest updates have broken the search function for reasons unknown so there are two possible causes (database corruption being the other) in Win 10. I think this is the first case I've seen on the Mac of this though, so I suspect that the issue is possibly corruption in the ~/.config/Fritzing directory. Also (assuming you are using Fritzing .93b) it updates the parts database from github at startup and if that gets interrupted that can corrupt the parts database. The github updating has been a problem on some of the older Macs lately but that usually hangs the app and turning off networking so it doesn't try the update has fixed that for some of the folks. Hope some part of this helps!
Peter