Can't block pop up ads on Safari 

Intrusive ads are part of being online. An ad blocker will take care of most of them.

We use the free K-Block! on all of our devices (iPhones, iPads, Macs). You can get it from the App Store.

Ka-Block! on the Mac App StoreApplehttps://apps.apple.com › app › ka-block

I wish I had a solution - I've done all those things and still some sites will do what you describe - if I click on a page, another tab opens up that I have no interest in. I searched a little online and found a Business Insider article for Macs, and it advised the same as you have done. Here it is, in case you want to read it:

https://www.businessinsider.com/guides/tech/how-to-block-pop-ups-on-mac

But the reason I'm sharing this is that they have a parallel article for the iPad, where, if you are still having pop-ups after taking all the steps described, they recommend clearing the history and website data:

https://www.businessinsider.com/guides/tech/how-to-block-pop-ups-on-ipad

Not sure why they don't recommend it for a Mac, except that maybe it's more complicated. Here's what I know about:

Website data (cookies): Safari/Settings/Privacy/Manage Website Data/Remove or Remove All

History: History/Clear History

Caches: For this you have to enable the Develop menu in the menu bar:

Safari/Settings/Advanced/Show Features for Web Developers (at the bottom).

Once you have that, the Develop menu has the option to Empty Caches.

I haven't tried any of this clearing/emptying business long enough to know if it blocks any pop-ups, but it's possible, I guess.

I use Safari on a limited basis.

I use to use Firefox and then switched to Chrome but found I was getting more spam after switching to Chrome on sites I was looking at, so I switched Brave and the spam has somewhat stopped and the ads and popups stopped.

Just my two cents worth

Brave is indeed a good choice. It has its own ad blocker built in.

Can you describe how the ads pop up? Do they open in new windows?

Sorry it wasn't more helpful. At least you've ruled out some things. Best of luck!