@jonwatson In "C:\Users\yourusername\AppData\Roaming\Opera Software" and "C:\Users\yourusername\AppData\Local\Opera Software", rename the "Opera Stable" folder to "Opera Stable old". Then, start Opera to start with fresh data and test if it still has the error. When you're done testing, you can delete the new Opera Stable folders and rename the old ones back.
