Can not upload images via editor | froala error 500

Your software
My Mautic version is: 4.4.7
My PHP version is: 8.0
My Database type and version is: MariaDB 10.3.38

Your problem
When I try to upload an Image via the Editor, I get an error 500 from froala.com. Why is it even contacting froala?

froala-upload-error-img
froala-upload-error

Have same problem. Is any solution?
Why use a third-party service at all if I have my own server?