Looks like the built-in web browser is WebKit based (recognisable by its web inspector)
I never managed to make Netflix work properly on Linux’ webkit browsers. Widevine only seems to work with Chromium and Gecko based browsers.
According to omglinux, VanillaOS is a Ubuntu based Linux with an immutable file system (first time I ever hear of this).
To be honest, the only thing I care of this days is a good OS for my RaspberryPis.
Immutable OS’ are really cool and are probably going to be the future of Linux desktop computing as they are much more stable and reliable as well as removing a big maintenance burden on the distro devs by shipping most of the software via Flatpaks.
If you’re interested, there is NixOS, Fedora Silverblue, SUSE MicroOS, VanillaOS are the big names at the moment I also suggest this read for some general info about how they work https://tesk.page/2023/08/29/misconceptions-about-immutable-distributions.html
