Huh, that's a new one. Thanksnfor bringing this to my attention.
This is what I managed to scour from the websites:
"It is more likely that your NWJS is too new, than too old. Rpgmaker MV hasn't been updated in quite a while.
It is indeed possible to have a too new version of NWJS. I had this happen when I downloaded a game made by someone else, and they been working in a verer version of NWJS then I did. However, I only got a popup, but could still play the game.
You could try uninstalling NWJS and then try again. RPG maker should automatically re-install the right version of NWJS the next time you test your game. (When you reinstalled RPG maker, NWJS was untouched. That did not get uninstalled and reinstalled too, because it isn't part of the RPG maker installment.)"