It's not good; people use Electron instead of XULRunner because XULRunner was barely maintained. It would randomly stop working on major Firefox releases, and w

It's not good; people use Electron instead of XULRunner because XULRunner was barely maintained. It would randomly stop working on major Firefox releases, and would stay broken for weeks, because nobody noticed or cared that XULRunner didn't work, as long as core Firefox kept working. Even when it did work, working with XPCOM sucked. Positron https://github.com/mozilla/positron https://github.com/mozilla/positron is the new XULRunner. WIP, doesn't actually work yet. :-(