We probably should have seen this coming: Firefox users, get ready for ads in your browser. I don’t think AdBlock or it’s friends will help you with this. Granted, it’s not as if you have no options at all, but they won’t be easy to find or use.
So your options now are Pale Moon, Seamonkey, or any of a half-dozen other derivative projects, depending on the OS you use. I suspect some of the various Linux distributions will chop out that functionality, as is their right under the licensing.
If you switch over to Chrome, you still have to deal with Google tracking you like a mean bloodhound. It’s getting harder and harder to escape the greedy corporate jerks these days. This is partly why I love Lynx (plain text browser) and a few other similar projects.