It would be too bad. I have enjoyed using Opera for years, along with the Mozilla browsers. If FB acquires it I, at least, will refuse upgrades or just delete it. By the way how does one block Google?
In your Opera’s toolbar, go to Tools/Advanced/Cookies, scroll thru all of the entries, and delete *everything* related to Google/Chrome etc. Many of the condensed [+] cookies need to be opened so you can delete each entry, or some might survive. In recent Opera versions, deleting the main entry does it; older versions required deleting all entries under the [+]. It changes to open when you see [-].
Keep scrolling and delete all of the various website entries for Google/Chrome etc, too. You’ll be stunned at what’s in that Cookies drop-down menu.
What version are you using? It’s in the toolbar under Help/ About.