It is not a Linux distro. It is not a Linux at all; it is a completely different, independent OS. It is not a Unix at all: it's an independent ground-up C++ OS that implements a lot of POSIX-type APIs to make it easier to port Unix apps.
Docker is literally a Linux native tool that is for Linux only. The only way Docker works on anything that isn't Linux is by running a Linux VM, containing Alpine.
It is not a Linux and no you cannot do Linux things with it like run Linux containers, because to run Linux containers you need Linux and this is not a Linux.
I am trying to emphasize this because your question seems to be asking "what kind of Linux is this?" and this is a category error.
> The only way Docker works on anything that isn't Linux is by running a Linux VM, containing Alpine.
Sorry but this is demonstrably false. Not only is Alpine not a requirement in the slightest, Windows Server's own containers work as a backend for Docker just fine.
Docker is literally a Linux native tool that is for Linux only. The only way Docker works on anything that isn't Linux is by running a Linux VM, containing Alpine.
It is not a Linux and no you cannot do Linux things with it like run Linux containers, because to run Linux containers you need Linux and this is not a Linux.
I am trying to emphasize this because your question seems to be asking "what kind of Linux is this?" and this is a category error.
https://en.wikipedia.org/wiki/Category_mistake
Or, as ESR originally put it, it's an X/Y problem:
https://mywiki.wooledge.org/XyProblem
Yes, a Firefox port became available recently. I don't know if it can run Zoom. I go out of my way to avoid Zoom if I possibly can.