Chrome's V8 and Safari WebKit are not the only way to run JavaScript...
A very extensive summary of JavaScript runtime engines...
The many, many, many JavaScript runtimes of the last decade • Buttondown
JavaScript runtimes (and engines in equal measure), enabling us to run JavaScript in all manner of contexts with precise fitness for task. Through these, we've seen the language spread to the Cloud, the edge, Smart TVs, mobile devices, and even microcontrollers.