mozilla (firefox/thunderbird) crashes randomly for seemingly no reason

[Leon Adato]

mozilla-based apps (firefox/thunderbird) crash randomly for seemingly no reason.

Happens multiple times per day but not repeatable. Shortly after mozilla apps crash, Chrome crashes as well.

Happens on primary desktop. Have replaced ALL hardware but the problem "followed" me to the new system.

Happened on Kubuntu 15.10 and now Ubuntu 16.04

Happens (almost) regardless of which tabs I'm running in chrome/firefox.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: firefox 46.0.1+build1-0ubuntu0.16.04.2
ProcVersionSignature: Ubuntu 4.4.0-22.40-generic 4.4.8
Uname: Linux 4.4.0-22-generic x86_64
AddonCompatCheckDisabled: False
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC2: leon 1970 F.... pulseaudio
 /dev/snd/controlC0: leon 1970 F.... pulseaudio
 /dev/snd/controlC1: leon 1970 F.... pulseaudio
BuildID: 20160511223818
Channel: Unavailable
CurrentDesktop: Unity
Date: Fri May 27 11:33:52 2016
Extensions: extensions.sqlite corrupt or missing
ForcedLayersAccel: False
IfupdownConfig:
 # interfaces(5) file used by ifup(8) and ifdown(8)
 auto lo
 iface lo inet loopback
IncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite)
InstallationDate: Installed on 2016-05-08 (19 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
IpRoute:
 default via 192.168.101.1 dev enp2s0 proto static metric 100
 169.254.0.0/16 dev enp2s0 scope link metric 1000
 192.168.101.0/24 dev enp2s0 proto kernel scope link src 192.168.101.102 metric 100
IwConfig:
 enp2s0 no wireless extensions.

 lo no wireless extensions.
Locales: extensions.sqlite corrupt or missing
MostRecentCrashID: bp-3a659447-24bb-4301-bb25-fed2c2160527
PrefSources:
 prefs.js
 [Profile]/<email address hidden>/defaults/preferences/defaults.js
Profiles: Profile0 (Default) - LastVersion=46.0.1/20160511223818
RfKill:

RunningIncompatibleAddons: False
SourcePackage: firefox
Themes: extensions.sqlite corrupt or missing
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/03/2014
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 2501
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: M5A99X EVO R2.0
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev 1.xx
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: To Be Filled By O.E.M.
dmi.chassis.version: To Be Filled By O.E.M.
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr2501:bd04/03/2014:svnTobefilledbyO.E.M.:pnTobefilledbyO.E.M.:pvrTobefilledbyO.E.M.:rvnASUSTeKCOMPUTERINC.:rnM5A99XEVOR2.0:rvrRev1.xx:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.:
dmi.product.name: To be filled by O.E.M.
dmi.product.version: To be filled by O.E.M.
dmi.sys.vendor: To be filled by O.E.M.

[Leon Adato (adatole)]

Crash report from firefox

[Leon Adato (adatole)]

crash report from Thunderbird

[Leon Adato (adatole)]

Note that once crashed, I'm not able to run firefox/thunderbird/chrome with any stability until a full system reboot.

[Leon Adato (adatole)]

Another crash. Attaching crash report as well as syslog

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.