It&#x27;s been &quot;the same javascript everywhere&quot; mostly due to the ECMAScript group kinda stalling for the past 15 years. The stabilisation created through that has been useful, but the plan is to transition the spec onto a one-year update cycle.<p>That means that going forward we&#x27;ll likely have more feature mismatch between engines, making backward compatibility compilers pretty important.<p>I&#x27;m not entirely sure if that&#x27;s good or not.