I have Joomla 3.9.8 and JCE 2.7.14. I just noticed that the Crop and Resize feature for front-end editing are not working. When I clicked Crop or Resize, it blinked bur nothing happen. The Save button did not allow me to save (the cursor did not change to pointer).
I inspected the code and see two errors on the console said
1. Refused to apply style index.php:1 from 'http://example.com....' because its MIME type ('text/html') is not a supported stylesheet MIME type, and strict MIME checking is enabled.
2. Failed to load index.php:1 resource: the server responded with a status 500 (Internal Server Error)