First thing you need to do is to install the Opera add-on "Install Chrome Extensions", which allows you to install extensions from Google Chrome Web Store in your Opera browser.
Visit Screenbreak's page at the chrome web store and click "Add to Opera"
You will be then prompted to the installation page with the following process:
🎊 That's it, you have successfully installed our Extension and are ready to use Screenbreak.
💡 Bonus tip, pin our extension for ease of use: