On Sat, 16 Jun 2012 20:39:38 +0200
Julius Schwartzenberg <julius.schwartzenberg@...> wrote:

> E. Liddell wrote:
> > Note that Firefox 13 appears to need nspr 4.9.1 or better.
> 
> Are you sure about that version number? Even Precise still has 4.8.9 and
> Lucid has 4.8.6.

I'm a Gentoo user, and 4.9.1 is what's specified by our package manager:

akio ~ # cat /usr/portage/www-client/firefox/firefox-13.0.ebuild
[...]
RDEPEND="
        >=sys-devel/binutils-2.16.1
        >=dev-libs/nss-3.13.5
        >=dev-libs/nspr-4.9.1

Also see https://bugzilla.mozilla.org/show_bug.cgi?id=713229 , which specifies 
nspr 4.9 for Firefox 12, and https://bugzilla.mozilla.org/show_bug.cgi?id=713936 .
So, yes, 90%+ sure.  However, I don't know if the version difference has
anything to do with your bug or not (I'm still on Firefox 12 and tend to avoid
Flash like the plague).