busler

I filled in the form. Thanks for the help. Please let me know if you need anything else.

I disabled the Black Studio TinyMCE plugin and still had the same problem with the blank screen. Are there other plugins known to have issues with the theme?

I have not seen any console errors on the customizer page. Here is a link to what it looks like: https://pasteboard.co/KirAVst.jpg

I am using the following:
Wordpress – 5.8
PHP – 7.4.22
Responsive Pro – No

Once we figure out what is wrong with the customizer page, I should be able to use the steps you gave to adjust the appearance of the header.