PeerTube Companion is an experimental WebExtension aiming to improve user experience with PeerTube. Right now, the extension redirects to a PeerTube version of a video, when trying to reach it from YouTube, if it's available on PeerTube.
Predirect Alternatives
Predirect is described as 'A open source manifest v3 web extension with minimal permissions that automatically redirects popular sites to privacy friendly frontends and backends' and is a Privacy Tool in the web browsers category. There are more than 10 alternatives to Predirect for a variety of platforms, including Mozilla Firefox, Google Chrome, Web-based, Vivaldi and Linux apps. The best Predirect alternative is LibRedirect, which is both free and Open Source. Other great apps like Predirect are Privacy Redirect, Redirector, Anonymous Redirect Links and YT Siphon.