You can get 1080p with Netflix or Amazon Prime in Firefox on Linux. It just requires some addons to modify their client app js (because the DRM verification level is high enough, it's only their frontend that disables this)

I already get 1080p on Netflix in Firefox on Linux.

However, Amazon Prime on the same setup gets me 720p at most. (This is a regression because I _know_ I used to watch the first few seasons of The Expanse in 1080.)

Which add-ons allow you to watch Prime in 1080p on Linux? I wasn't able to find them.

Same experience here, Netflix works without too much hassle, but Prime is limited to a much lower bitrate than on Windows.

At one point I experimented a bit with making an addon myself, and it's possible to intercept the requests and spoof the UA/platform to get URLs for the HD streams, but then it goes to VMP/widevine and is a bit beyond my abilities. Best I could get was for the HD quality option to appear in the UI, but with a complaint that it wouldn't work because I needed to update or use a different browser.

Now pretty much the only time I use Prime video is for the occasional watchparty, and I'll just pirate the stuff I want to see in HD.

Except that the WideVine DRM library under Linux only does software decoding, so HD video tends to stutter according to the issue logs on said extensions on GitHub. Assuming you get it to work at all of course.

I haven't had any lag issues with it and my HTPC is running a 12-year-old processor with a 10-year-old AMD GPU. Maybe it's an Intel or Nvidia driver issue?

I'm running KDE and have it configured to disable the compositor when an app goes full screen. Maybe that's your issue? Try turning off desktop effects and screwing around with your compositor settings.

Edit: I want to point out that since my GPU can't handle 4k the desktop resolution is limited to ~2k (whatever the highest was that it can handle at 60Hz--I forget now haha).

I assume that that was a point in regards with $100 mini-pc (think ARM-based one). Your 12-year old device likely has more performance comparing to those modern and cheap pc's.

You can watch HD in the Netflix app on Windows if your hardware supports HDCP.

Edge on Windows also gets HD from Netflix and Amazon, because it uses the same DRM pipeline as the app does (Microsoft PlayReady).

There's no exemption from the DRM rules here, Edge and the app implement hardware backed DRM systems.

WideVine is level3 for browsers on the Desktop: https://go.buydrm.com/thedrmblog/why-google-widevines-drm-is...

I guess Windows streaming is going via PlayReady then.

Widevine is not used by Edge for Windows, as you say PlayReady is.

(Well, Widevine actually is also present for a site to use if you really want to, but other than being too lazy to have two license servers there's very little reason why you would.)

Microsoft have not ported PlayReady to other OSes, so Edge for Mac/Linux does use Widevine and gets Level 3.

Thanks for pointing this out, I wasn’t aware.