Massive performance regressions and faulty rendering.

[Jo-Erlend Schinstad]

With the Firefox 60 upgrade, Firefox renders text improperly, to the extent that text is sometimes unreadable. Videos can no longer be viewed in full screen without lots of skipped frames. I've never had any of these issues with previous versions.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: firefox 60.0+build2-0ubuntu0.14.04.1
ProcVersionSignature: Ubuntu 4.4.0-124.148~14.04.1-generic 4.4.117
Uname: Linux 4.4.0-124-generic x86_64
AddonCompatCheckDisabled: False
ApportVersion: 2.14.1-0ubuntu3.27
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: jo-erlend 2735 F.... pulseaudio
BuildID: 20180509235355
Channel: Unavailable
CurrentDesktop: Unity
Date: Thu May 17 12:50:30 2018
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 2017-01-25 (477 days ago)
InstallationMedia: Ubuntu 14.04.5 LTS "Trusty Tahr" - Release amd64 (20160803)
IpRoute:
 default via 192.168.0.1 dev eth0 proto static
 192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.105 metric 1
 192.168.0.0/24 dev wlan0 proto kernel scope link src 192.168.0.102 metric 9
 192.168.122.0/24 dev virbr0 proto kernel scope link src 192.168.122.1
Locales: extensions.sqlite corrupt or missing
Plugins: Shockwave Flash - /usr/lib/flashplugin-installer/libflashplayer.so
PrefSources: prefs.js
Profiles: Profile0 (Default) - LastVersion=60.0/20180509235355 (In use)
RunningIncompatibleAddons: False
SourcePackage: firefox
Themes: extensions.sqlite corrupt or missing
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/18/2016
dmi.bios.vendor: LENOVO
dmi.bios.version: D7CN30WW(V3.03)
dmi.board.asset.tag: NO Asset Tag
dmi.board.name: Lenovo E51-80
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40705 WIN
dmi.chassis.asset.tag: NO Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Lenovo E51-80
dmi.modalias: dmi:bvnLENOVO:bvrD7CN30WW(V3.03):bd04/18/2016:svnLENOVO:pn80QB:pvrLenovoE51-80:rvnLENOVO:rnLenovoE51-80:rvrSDK0J40705WIN:cvnLENOVO:ct10:cvrLenovoE51-80:
dmi.product.name: 80QB
dmi.product.version: Lenovo E51-80
dmi.sys.vendor: LENOVO