These things remind me a lot of the "Chrome Web Apps" and "Firefox apps" you used to be able to save to your desktop as .desktop files and launch "web apps" without the "rest of the browser" along for the ride. Which helped sometimes with Chrome on certain sites, because I do have somewhat of a hefty load in regards to extensions.
```
flatpak install nuvola eu.tiliado.NuvolaAppGoogleCalendar
flatpak install nuvola eu.tiliado.NuvolaAppPocketCasts
flatpak install nuvola eu.tiliado.NuvolaAppSpotify
flatpak install nuvola eu.tiliado.NuvolaAppYoutube
```