Hey,
My company has an old WP website using the Stratus theme that was bought from ThemeForest. After updating the WP version to 5.5.1 most of the CSS/JS broke in the admin panel. I managed to fix some stuff, but one big issue persisted. When editing existing pages, the contents in them won’t show up and the page is simply blank.
I then figured out that the Stratus theme needs to be updated with the Envato plugin and ours is very outdated. So fat we used version 2.0.1, but the latest version is 3.8.13. After installing and setting up the plugin and updating the theme, however, all of the style and content for the page is lost. Style is something I could maybe fix, but why is all the text gone from all the pages as well?
Let me know if there is some more information you would need to help me solve this.