Please explain the problem in detail. What happens? What is the exact error messages?

Go to the Mozilla Add-ons Web Page {web Link} (There’s a lot of good stuff here) and search for a good ad blocker.

There are no error messages, just a lot of crap sponsored content I want to block.

sparkwizard said

just a lot of crap sponsored content I want to block.

Hello sparkwizard,

Would you please take a look at this article :

https://www.ghacks.net/2018/05/02/firefox-60-sponsored-content-for-us-users/

Also see :

https://blog.mozilla.org/futurereleases/2018/04/30/a-privacy-conscious-approach-to-sponsored-content/

You could also consider this add-on :

https://addons.mozilla.org/en-US/firefox/addon/ublock-origin/

See (in case this applies to your situation) : https://www.reddit.com/r/firefox/comments/8tsz9g/is_there_any_addon_or_ublockorigin_filter_to/

I have already unchecked the boxes in firefox to block sponsored content from pocket, but that did not block all of the garbage sponsored content from other providers. My adblock plus was blocking it until firefox did something to break it with the new update.

Firefox 66.0.4 is now available.

Open up Help > About Firefox the check for the update and install it. Then restart Firefox.

sparkwizard said

My adblock plus was blocking it until firefox did something to break it with the new update.

That was caused by an unforeseen technical problem …..

Please see : https://blog.mozilla.org/addons/2019/05/04/update-regarding-add-ons-in-firefox/comment-page-5/

And it's now fixed with the release of Firefox version 66.0.4 (see "the-edmeister's" post)

Already tried firefox 66.0.4. It did not fix the problem, adblock still will not install.

sparkwizard said

Already tried firefox 66.0.4. It did not fix the problem, adblock still will not install.

Would you try again please  ?

I assume that you're talking about Adblock Plus, cause Adblock is not on the official addons.mozilla.org page :

https://addons.mozilla.org/en-US/firefox/addon/adblock-plus/