I'm also having the same issue as the user post linked below. Suddenly, after several years of using JCE, all the headings, font styles options etc are showing advanced. before the item like advanced.h1. I followed your steps below - uninstall, reinstall. Cleared both Joomla system cache and browser cache. But I'm still getting these same advanced. items. I regularly keep the backend up to date but have not added content recently so I'm not sure when this started, but I'm thinking it was recent. Joomla 3.9.5 and JCE Pro 2.7.11.



similar resolved post mentioned:
https://www.joomlacontenteditor.net/support/forum/80814

thanks for your help

OK, I installed the RC4 version you sent. No luck. I then completely uninstalled JCE, cleared cache, etc then reinstalled the RC. Still no luck. (even tried it on a fresh browser that never saw the site before). Front end editing still shows this "advanced." prefix described above. Backend editing w/JCE appears as expected. The front end use of JCE is actually most important to me because my client will be using it to create articles.

Next steps?

Thank you very much Ryan. This seems to have fixed the issue! Much appreciated!