I am analyzing the patches listed in the previously linked series.microb2 file. That list contains 114 patches. These are the patches I have analyzed so far and what I have found.

http://browser.garage.maemo.org/docs/patches.html is also potentially useful since it describes some of the patches.
Also https://bugzilla.mozilla.org/show_bug.cgi?id=401821 has lots of links to useful bugs in bugzilla.mozilla.org.

Patches that match to a bugzilla.mozilla.org bug: (the ones I have found so far anyway)
002_drawingMissingGlyphs.diff bug 463927 (fix never committed, looks easy to forward-port)
010_BUG376279_security_cross_compile.diff bug 376279 (build system has been changed so much in FF24 its unclear if this is needed or not)
010_BUILDFIX_embedding_tests.diff bug 93213 (related to the now removed gtk embedding stuff, will need to be sorted out as part of bringing that back)
020_nspr_dpkg_cross.diff bug 376256 (build system has been changed so much in FF24 its unclear if this is needed or not)
020_nsWindowCreator2_iface.diff bug 437018 (related to the now removed gtk embedding stuff, will need to be sorted out as part of bringing that back)
023_PC_CONFIG_sqlite_neededby_libsoftokn.diff bug 463928 (unclear if we still need this for Fremantle or not)
030_host_libidl_dpkg_cross.diff bug 401831 (build system has been changed so much in FF24 its unclear if this is needed or not)
130_456015.certview.diff bug 456015 (fix never completed, looks easy to forward port)

More analysis to come later.