I had this issue before and it was never resolved. I thought it was due to an error I was getting when upgrading my PHP version, but that was unrelated.
Currently, i’m on MODX 2.8.1 and PHP 7.3. I’m trying to update the RTE Extra from v1.2.1-pl to the current v1.4.0. But every time I do this, the content area of my resources just disappears. I’m not sure how to proceed. The Modx Error logs and server logs show nothing either. So I’m out of ideas.
I’d try clearing your browser cache (you could also try in a private/incognito window).
If that doesn’t work, check your browser console and see what error you’re getting when you load the page.
yes, this did fix the problem. It was a browser caching issue. Is there a way to globally refresh or force the browser to refresh for my other users that may not know how to do this?