Julien, your patch above is just inserting an error into browser_dom_window.openURI - there is no
property 'this.browser'.  So any error, or perhaps a simple 'return null;' at that point may reproduce
the 'fix' you see.  I would be curious to know what behavior results from 'return null;' at that point.

From my reading though, what Michael Layzell indicated is that opener needs to be set on the new window,
not the old one.  Scott and I tried a couple of ways of doing exactly that, and the crash remained, so in
my view, this crash that we're seeing is the one from
https://bugzilla.mozilla.org/show_bug.cgi?id=1334086 not the one from
https://bugzilla.mozilla.org/show_bug.cgi?id=1316104