> dustin@euclid ~/tmp/mime-types-9 $ grep ^image/jpeg /etc/mime.types > image/jpeg jpe jpeg jpg But on CentOS/RHEL 6.2: > image/jpeg jpeg jpg jpe jfif And on Ubuntu 12.0.4: >image/jpeg jpeg jpg jpe And on OS X 10.7: > image/jpeg jpeg jpg jpe jfif The visible result of this is that Firefox will tend to name JPEGs "foo.jpe" when saving them, similar to https://bugzilla.mozilla.org/show_bug.cgi?id=414201 The more immediate consequence is that the docshell/test/unit/test_bug414201_jfif.js test fails when run on a Gentoo system. I'm discussing with the Mozilla developers whether this is an expected failure of the test (that is, whether the test is testing the Firefox codebase only, or also the system it runs on).
Heh, tricky. I didn't know the order of extensions mattered at all! Let me see if there's a way to rejigger my script to make this better.
Yeah, I can't actually find *any* documentation of this file, but "Firefox thinks so" is close enough to "Netscape thought so" that it's probably authoritative.
extensions in /etc/mime.types (from app-misc/mime-types) sorted alphabetically, not by priority. for example: image/jpeg jpe jpeg jpg application/vnd.ms-excel xla xlb xlc xlm xls xlt xlw ... must be: image/jpeg jpeg jpg jpe application/vnd.ms-excel xls lxb xlm xla xlc xlt xlw ...
https://packages.debian.org/en/bullseye/media-types "...and their usual file extension. " USUAL... "... file is compiled by hand ..." BY HAND...
Resolved by app-misc/mime-types-2.1.53. See bug 762958 for further information.