@Hattyfatner it's a shame the reply that was previously here was deleted as it did help to some extent.
I looked into the setting and followed some of of the instruction carefully but for some bizzarre reason, the post is deleted.
But it is a major concern for the software that it was almost impossible to do and took literally hours and hours.
Add to that that I'm a software engineer and it beggars belief anyone else could ever manage it.
The browser is essentially blocking adverts behind a convoluted mess of a settings system of menus that are extremely confusing and opaque.
But I have spent hours and hours studying it to find how to enable advertising and find the hundreds of cookies that every website seems able to give you whether you clicked anything or not.
So well done Opera, you've almost completely destroyed the codebase.
What will your next trick be...?