
It could be down to one of the extensions I have installed, though (I'll try it with extensions disabled when I'm back home later, if I remember).
However, it works OK on Fennec (mobile FF) on my mobile.
I wouldn't expect much modern stuff to work on IE...MS are actually now actively trying to get people to stop using it...
Edit: Nope, no go in PM 28.2.2...web console reports "SyntaxError: missing ( before catch" in "robots2.js:462:9" when initially loading the page, but nothing more when clicking on buttons.
( , Sun 10 Feb 2019, 22:30, Reply)

Including numerous companies that have internal business-critical systems that will only run on a specific version of IE...
( , Sun 10 Feb 2019, 23:06, Reply)

That's the opposite of what exception handling's supposed to do!
( , Mon 11 Feb 2019, 12:49, Reply)