Sorry, but how do you actually turn this on?
I installed Tampermonkey and copied the script in and the dashboard says it's enabled, but Tampermonkey says no scripts are running and a search on DuckDuckGo just searches on DuckDuckGo.
For this to happen, both Opera and Ecosia need to want it, and it has to be profitable for both.
So did you already contacted Ecosia? What they say about it? Di dthey already try an agreement with Opera?