One example is a script to quickly grab the URL of the current tab and send it to mpv¹ for playing or yt-dlp² for downloading. Or send some JavaScript to that same tab. Or grab the URLs and titles of all tabs in all windows that match a specific domain, close them, and then reopen them together in a brand new window (or save it to clipboard to send someone). Alfred³ has a ton of automations that allow you to do that without having to code it yourself.