I have made something similar (https://easylang.online/ide/ https://easylang.online/ide/). It is a language of its own, which is compiled and interpreted by WAS

I have made something similar (https://easylang.online/ide/ https://easylang.online/ide/). It is a language of its own, which is compiled and interpreted by WASM. The problem with hanging in endless loops is solved by running the interpreter in a "web worker" that can be killed and restarted at any time.