When a certain page or function fails because of cached data or scripts, we need to clear the browser cache, especially "Cached images and files".
1. Clear Browsing Data can be accessed via Firefox's dropdown menu, Settings.
2. Select Privacy and Security on the left and Under Cookies and Site Data, please click on Clear Data...
We also recommend letting Firefox to delete cookies and site data when it is closed.
3. Please close the browser completely after you clear browsing data and re-open it to try the page/function again.
See Also: