No server does any of the work. Your browser downloads an emulator compiled
to WebAssembly and a Linux disk image, then executes every guest instruction
locally on V8. Nothing you type leaves the machine.
Before you press start, honestly:
The download is large. Exact size is read from the manifest below.
It is emulation, not virtualisation. There is no KVM in a browser, so
every instruction is translated. Expect it to feel like a slow machine
from a long time ago.
Graphics are software-rendered. There is no GPU inside a WebAssembly
process, so the desktop is drawn pixel by pixel on the emulated CPU.
The download is cached. A second visit starts far faster.