Your software
My Mautic version is: 5.2.4
My PHP version is: 8.3.19
My Database type and version is: mysql Ver 15.1 Distrib 10.11.8-MariaDB
Your problem
My problem is: Updating to 5.2.4 with no problem.
Since some versions the CKEditor was shown blank window if loading assets.
Found a solution with
Did you clear your Mautic cache in all that process, by any chance? And your browser cache? These two have caught me out in the past with cached JS/CSS files.
On this server, I’ve two Mautic installations, and both facing this problem. Rolling back some files with executing some commands have helped, but we’re not sure, what it was.