https://bugzilla.mozilla.org/show_bug.cgi?id=1352449
Mozilla patch that's been in the code since Firefox 55. Seems like there have been no ill effects from implementing it, and it would only increase the portability of the UXP code. All the Solaris Firefox repos I've seen implement some variation on the jsexn patch, and this seems to be the cleanest version of it.
I can add ifdefs if needed or there are performance concerns associated with this patch, but I get the impression this alignment backlog issue might affect a few platforms other than Solaris, though none were named. Otherwise I think they wouldn't have used "platforms that need it" in plural form or failed to ifdef it.
