Your software
My Mautic version is: 5.2.3
My PHP version is: 8.3
My Database type and version is: MariaDB 10.6.21
Your problem
I am migrating from Mautic 4.4.13 to 5.2.3. My understanding is that email templates can only be transferred manually. I copy the Builder code of a given template in the old Mautic version to the new version. I use the Blank theme. After copying the code to the new version and clicking “Apply Changes”, the Builder window will not close. Therefore, I cannot get to the previous window to save the template. What could be the cause of this?