Closest I can think of is efforts like https://jerryscript.net/ https://jerryscript.net/ and https://duktape.org/ https://duktape.org/ – but the challenge isn't

Closest I can think of is efforts like https://jerryscript.net/ https://jerryscript.net/ and https://duktape.org/ https://duktape.org/ – but the challenge isn't in the language itself really, but in the web API:s that gets added to it. Eg. Node.js doesn't have WebUSB either :)