Hi Tom,
Thanks for posting in.
WordFence has a built in caching feature. And Cornerstone doesn’t work well with cached resources. Since you have installed WordFence, please clear your plugin cache first (WordFence > Performance Setup) before testing your site. After doing WordPress core, themes and plugin updates, we highly recommend that clear your plugin cache as well. This can cause the changes to not take place on the front end. It will eventually show up when the cache regenerates, but it’s not ideal if you’re looking to see your changes immediately.
Hope this helps. Please let us know how it goes.
Thanks,
Joao