For some reason I thought this was gonna be a demo of running docker in your browser through WASM. kinda disappointed that's not it :p
We have technology like WebVM [1] (from leaningtech / CheerP) or Copy86 [2] that already allows x86 machine code execution/emulation on the web. If you add an OCI client layer on top that is executable in the browser, it should be possible to run Docker containers in the browser.