If you’re using Brave on Ubuntu and can’t play DRM-protected content (Netflix, Crunchyroll, HBO Max, Spotify Web, etc.), the issue is almost always the Widevine DRM module.
In many cases, Brave simply doesn’t download it automatically — especially on fresh or minimal installations.
Fortunately, you can manually install Widevine using the official Google Chrome package without installing Chrome. This guide shows the exact steps.