In the RTE there are a few predefined block formats like "Headings", "paragraph" and so. Is it possible to do new block formats, and customize the markup that wraps them?
Im doing a newsletter and I would like to use tables around each paragraph
There is a button called Insert custom element and there you can add custom para-templates for RTE, however it's possible that you need to enable it and add new 'items'.
Here (DE) in section Einfügen über User-Elemente you have a description for that. Presented snippets should be placed in the PageTS of highest (root) page.