Hello,
in the documentation for the grapeJS Email builder it states the following:
At present, Mautic won’t process the
<mj-head>tags. None of the<mj-attribuites>run, so you have to do all styling inline.
On this forum however I have seen multiple people recommend to do styling using the mj-head section in themes. Now my question is if this limitation has since been fixed and the documentation just hasn’t updated yet, or if the forum posts are refering to maybe pre exporting mjml to html in some other tool.