DRM content works with Firefox on Linux. You normally need to enable the content from the navigation bar usually found where the https lock icon is before the web address

Sorry I disappeared for a few days. I was running against a deadline for the aforementioned client.

Anyway, I found that DRM has been working in Firefox for a while. It worked, but I had no sound. Oh. It's too bad the Firefox team are jerks and want to force Pulseaudio on everyone. No way. I've always had a lot of trouble with Pulseaudio.

So I found Waterfox, which is like a new version of Firefox except it fully supports ALSA. I can view and hear DRM content perfectly now.

Problem solved. Thank you very much for all the help.

Install IdeaNova DRM Extension
 

I just discovered a Chromium plugin which allows me to play DRM video right away.

Install IdeaNova DRM Extension. In the Netherlands, where I live, our national broadcast company, NPO, provides only DRM video :( I was installing Ubuntu for a friend. I thought I had adjusted and personalized everything when I noticed I can't play NPO video! Bummer! But for now it works and I hope the plugin keeps up to date!

TBH, getting WideVine to work in Chromium is as simple as 'poaching' the WidevineCdm directory from a current copy of Chrome, and just dropping it into the main 'chromium' directory. If Chromium is asked to open a site that requires DRM, it'll find it and pick it up automatically.

The reason this works? Simple.....because Chromium is the default code-base from which all the other 'clones' take theirs. Even Chrome; it, too, is a 'clone' of Chromium, albeit with Google's own, proprietary, 'nosy', tracking/telemetry stuff added to it.

When Chrome was announced back in Autumn 2008, they set up the Chromium Project at the same-time, as a publicly-scrutinised, open-source entity. The Project is essentially Google's browser R & D department, with semi-autonomous 'build-bots' churning out dozens of updated builds every 24 hrs. Every time a 'patch' is submitted to the upstream build-process repo, it triggers the build-bots into life, and off they go again....

The Chromium dev community is world-wide, and "on-the-go" ALL the time, 24/7.

I've even built a 'portable' version of UnGoogled Chromium with Widevine built-in for the Puppy Linux community. Despite having all ties cut with Google's proprietary, corporate software, this still works. It's quite popular, too!

Mike. :hattip:

Thanks so much. Still most people want to have it work out the box and are not capable to work on the back side of software.