@PawGo, does this mean that the owner has decided to introduce this feature on their site? Since you know what this is about, how can an ordinary user block such things?
Yes, it is managed by site owner/developer.
I am not sure if you may disable it on browser level (maybe some browsers has that feature, I do not know), but after you reject it, it should not appear anymore. But if you use private mode or clear browsing data, maybe it will be proposed again.
It will reappear after 2-3 days, and even if you accept it , and use the app (it works like a shortcut), it will ask you again and again.