I'm not entirely sure. I believe it has to do with the DRM implementation. While Widewine is the DRM in Chrome and Firefox, Edge uses something different[1].

I've seen people talk about Chrome being able to handle 1080p in ChromeOS. So there seems to be more than just Netflix's choice involved here. Although I bet Microsoft being proactive helped. Definitely unclear.

Also I don't see any reason why Netflix wouldn't want to support 1080p in all the major browsers. The only downside might be excess bandwidth, but with the Open Connect Appliance being a thing, I doubt it is a big factor.

[1]: https://blogs.windows.com/windowsexperience/2016/07/13/get-b...

As far as I understand it, you need tight coupling between the browser and the OS to implement the sort of deep-reaching DRM that Netflix/Hollywood wants for 1080p. That would explain why Edge on Windows and Chrome on ChromeOS can do it.

Personally, I see it as a plus that my browser/OS combo does not support this. There have to be horrid security implications that just wait to be unturned.

Indeed: https://www.schneier.com/blog/archives/2007/02/drm_in_window...

Insistence on DRM ironically is causing the opposite effect - wider piracy of DRM-free versions.

If it's because of DRM, it's the fault of Netflix. No one stops them releasing their video DRM-free.

It's not the first time DRM hampers performance and thus degrades usability. It's by definition an anti-feature.