How to add custom meta tags for Seo purpose into a page….

Hi, I have created pages using the PageBuilder tool. I now want to manually add some custom markup to the pages to add semantic information to it (microformats, etc.). However, when I click “revert to editor” button all the work done in PageBuilder is gone.

Is there any way to have the page built with PageBuilder but at the same time add custom code to the underlying markup?

Thanks.