DnD Beyond Auto Source Filter by TechWitch

This extension helps you auto-filter by source book on dndbeyond.com so that you can easily ignore material from source books you don't own. Simply go to a dndbeyond.com page that has advanced filtering, filter by the source documents you own, and then open the extension settings in your browser to save the filter. It will then be automatically applied.

You can find the source books you own here: https://www.dndbeyond.com/account/marketplace