"legacy" email templates showing multiple "<style>.cke{visibility:hidden;}</style>"

Your software
My Mautic version is: 4.4.x (installed latest 4.4.6, and it still have the same behaviour)
My PHP version is: 7.4.33
My Database type and version is: 10.3.37-MariaDB-0ubuntu0.20.04.1

Your problem
My problem is: templates that were done and working perfectly on Mautic’s versions 3.x started producing multiple “.cke{visibility:hidden;}” just before the closing “” in channels > emails.

This happens, either by using GrapeJS, or by using the old editor, with all “legacy” templates that used to work.

These errors are showing in the log: no errors appear

Steps I have tried to fix the problem: the only way that I can remove those multiple entries is to enter into code view mode, and manually remove those entries that appear just before the closing

Is there anything that should be done besides appending ““builder”: [“legacy”, “grapesjsbuilder”],” to config.json, as stated in the documentation?

Thanks in advance for any advice on this. Best regards.