image from data url is not displayed

[vasaka]

Following data url is a rectangle on chrome, but firefox refuses to display it, telling that image contains error.

data:image/gif;base64,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

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: firefox 45.0.2+build1-0ubuntu0.15.10.1
ProcVersionSignature: Ubuntu 4.4.0-14.30~14.04.2-generic 4.4.5
Uname: Linux 4.4.0-14-generic x86_64
AddonCompatCheckDisabled: False
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: vasaka 2285 F.... pulseaudio
 /dev/snd/controlC1: vasaka 2285 F.... pulseaudio
BuildID: 20160413222546
Channel: Unavailable
CurrentDesktop: Unity
Date: Fri Apr 22 13:56:56 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 2016-04-01 (21 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
Locales: extensions.sqlite corrupt or missing
Plugins: iTunes Application Detector - /usr/lib/mozilla/plugins/librhythmbox-itms-detection-plugin.so (rhythmbox-mozilla)
PrefSources: prefs.js
Profiles: Profile0 (Default) - LastVersion=45.0.2/20160413222546 (In use)
RelatedPackageVersions: rhythmbox-mozilla 3.2.1-1ubuntu3.1
RunningIncompatibleAddons: False
SourcePackage: firefox
Themes: extensions.sqlite corrupt or missing
UpgradeStatus: Upgraded to wily on 2016-04-01 (20 days ago)
dmi.bios.date: 01/16/2015
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: G551JW.202
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: G551JW
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: 1.0
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTeK COMPUTER INC.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrG551JW.202:bd01/16/2015:svnASUSTeKCOMPUTERINC.:pnG551JW:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnG551JW:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:
dmi.product.name: G551JW
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK COMPUTER INC.