example, to run our Conway’s Game of Life demo with WebGPU enabled: Use --devtools=6080 to enable support for debugging pages with Firefox DevTools: Built servoshell yourself? When you build it yourself to set up your environment before continuing with the steps below. To build servoshell for your machine: There are multiple profiles available for build. debug is default profile if no profile is passed the shell.nix , change the line if ! [ -e /etc/NIXOS ]; then to if false; then to disable the support in shell.nix for producing binary artifacts that don't depend on the nix store. If you get this