Hi Matt, I'm thinking the "advanced" options menu has disappeared with the new version of the email editor, right? Where can get get the old "source code" option now?
If you are using a rich text module in your email you should still be able to access the source code of that text module in both the drag and custom email builder.
Drag and Drop:
Custom
Matthew Shepherd
Freelance HubSpot Consultant CRM Consultant | SEO Specialist
If you need access to modify all HTML elements of your email template you may need to create the template as a coded file. If you are using a drag and drop email template you could perhaps copy the HTML of that template and add it to a new coded file and modify from there. Here are some more resources on working with custom coded templates: