https://www.qwant.com/?q=firefox+without+DRM&client=ext-firefox-sb&t=web
this is a remarkably instructive series of links showing the path that led to LIBREWOLF having DRM inside it.
i'm pretty much done with working around this, adding a blocker to prevent spotify DRM previews has led to a substantial loss of performance of my nostr client and this never happened with brave.