In https://chat.mozilla.org/#/room/#necko:mozilla.org today :emilio was asking about an nsresult that https://james-ross.co.uk/mozilla/misc/nserror?0x805A2F9C was able to translate but https://www.oxymoronical.com/nsresult/ was not. In https://bugzilla.mozilla.org/show_bug.cgi?id=1686041#c8 I'd asked if the latter should be our canonical error result lookup location that might want to be updated, but since it doesn't know about the error but https://james-ross.co.uk/mozilla/misc/nserror does and claims it was last updated in 2011, perhaps it would make sense to add a searchfox error lookup mechanism.

I'd propose something like a search of nsresult:0x805A2F9C plus perhaps some kind of default heuristic for the default search mode where when we see a hex number we treat it as an nsresult and union the results of a fulltext search on the hex with a symbolic and fulltext search on the result of the nsresult lookup.