Solution to not display the form after Oracle SQL developer is changed to a Windows topic

After installing the latest oracle11g R2, open SQL developer and find that the interface is different from the previous one. I am not very used to it. I occasionally find that I can change the topic in the settings, so I changed the Windows topic, the result is that only the processes in the Task Manager are displayed, but the interface is never displayed. So I guess this must have been written in the configuration file. I went to the installation folder to find it one by one, but I still didn't find it. I accidentally searched a foreigner's article and said exactly this thing.

The original reference is as follows:

You can reset the system to factory defaults by deleting the system folder in the C: \ Documents and Settings \ <your connection> \ Application Data \ SQL developer \ This is a bit radical as it will delete your connections and any other settings you have made. i'm assuming you have not got a backup of your connections.
You can just delete the preferences file. This is in that system folder in a directory \ Application Data \ SQL developer \ system1.5.5.59.69 \ O. SQL ).11.1.1.59.69 and the file is product-preferences.xml
Have SQL developer closed when you do this and restart it after you have deleted the file.

But I couldn't find it. Maybe he was talking about the XP system. Finally, I found this directory:

C: \ Users \ <Name> \ appdata \ roaming \ SQL developer

Then to this subdirectory \ system1.5.5.59.69 \ O. sql0000.11.1.1.59.69 \, delete the product-preferences.xml file inside, restart SQL developer, success, thank you foreigners ~