I had used Firefox Sync to sync User Style Manager styles onto another computer. Great feature. I then disconnected Firefox Sync from both systems. I made changes to the User Styles in User Style Manager, and connected that computer to Firefox Sync again. A prompt asked if the styles should be overwritten on the server or if the local styles should be overwritten. I pressed the button to override the server's styles with the local styles. The opposite happened. The server styles overwrote all the local styles.
I had used Firefox Sync to sync User Style Manager styles onto another computer. Great feature. I then disconnected Firefox Sync from both systems. I made changes to the User Styles in User Style Manager, and connected that computer to Firefox Sync again. A prompt asked if the styles should be overwritten on the server or if the local styles should be overwritten. I pressed the button to override the server's styles with the local styles. The opposite happened. The server styles overwrote all the local styles.