Dingus (often) doesn't work in Firefox

[marijnh]

Loading https://spec.commonmark.org/dingus/ in Firefox, I usually get nothing in the preview area. The problem appears to be that the $('iframe').on('load', ... never fires (possibly because the frame is already loaded by the time the document ready callback runs), so the preview logic is simply never initialized. I guess this being a race also explains why it sometimes works (the chance seems to improve when I have devtools open, which possibly slows something down).

[jgm]

I see the same thing. Do you have a suggested fix?