The DOpus directive seems to accept any values, and since 3 was mentioned in the 13.12 release notes, I thought 11 (corresponding to Windows JScript engine version, not ES*) might make sense, but apparently it does not. Apart from the values 1 & 2 in Jon's screenshot, Windows probabaly treats anything >= 3, like 3, 4, 11, 129... the same (please test).
*: In another thread a poster mentioned Win11 is ES2024-compliant now, which is kinda misleading, but there is another 100% wrong statement in that post: JScript/WSH v5 is not ES v5 aka ES 2009, but demonstrably Microsoft's own version of ES3 (I have posts about this: 1, 2).
In my tests it (e.g. Win11 24H2) simply does not even support ES5, with or without JSCRIPTVER=3, 5, 20, 150.. Again, apart from very few trivial additions in Win11, we're still stuck with ~ES3.
There is, however, a newer JScript engine in Windows, which inded supports at least ES 9/2018, but that the devs probably overlooked it.