Open several existing classes so that there is more than one tab open at the top.
Select the first tab and make a change in the userClassName in the Config menu.
Click on the second tab and change the userClassName in the Config menu.
From the second tab, click the Save Project button. (The project can be saved and published with all the current changes.)
Now close each tab individually. The userClassName in the first tab will revert back to what it was originally.
Make sure to hit the Save Project button on each tab before closing them. This is mainly for File i/o changes on existing files that cause syncing issues with the secondary collection.
In this example, by changing the userClassName, the original file in the User's project path is deleted and a new one is created. On closing the tab, the secondary (hidden cache) collection overrides the changes in the user's project path.
Thanks for the input. I happened twice this morning when I was dealing with some issues with class linking. Now I'm having a hard time reproducing it. When I started closing tabs is when I notice that the userClassName was reverting back to its prior state. If I notice it again, I'll try to get more information for you.