getPreventDefault deprecation warning always logged to console

[avdd]

This message is always logged to the developer console, even on about:blank, when a key is first pressed:

Use of getPreventDefault() is deprecated. Use defaultPrevented instead.

Tested using new blank profile in safe mode. This occurs when the console is opened with a shortcut (F12), or by (re-)loading a page with the console open and then pressing a key with the content pane focused.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: firefox 35.0.1+build1-0ubuntu0.14.04.1
ProcVersionSignature: Ubuntu 3.13.0-45.74-generic 3.13.11-ckt13
Uname: Linux 3.13.0-45-generic x86_64
AddonCompatCheckDisabled: False
ApportVersion: 2.14.1-0ubuntu3.6
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: avdd 2211 F.... pulseaudio
BuildID: 20150125222008
Channel: Unavailable
CurrentDesktop: Unity
Date: Thu Feb 19 15:36:53 2015
DefaultProfileIncompatibleExtensions:
 Global Menu Bar integration - <email address hidden>
 Default - {972ce4c6-7e08-4474-a285-3208198ce6fd}
DefaultProfilePrefSources:
 prefs.js
 user.js
ForcedLayersAccel: False
IfupdownConfig:
 # interfaces(5) file used by ifup(8) and ifdown(8)
 auto lo
 iface lo inet loopback
InstallationDate: Installed on 2014-05-03 (291 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
IpRoute:
 default via 192.168.178.1 dev eth0 proto static
 192.168.178.0/24 dev eth0 proto kernel scope link src 192.168.178.20 metric 1
MostRecentCrashID: bp-39cb68f1-0f39-471b-863a-879bb2140901
Profile0IncompatibleExtensions:
 English (South Africa) Language Pack - <email address hidden>
 English (GB) Language Pack - <email address hidden>
 Japanese Language Pack - <email address hidden>
 Default - {972ce4c6-7e08-4474-a285-3208198ce6fd}
Profile0PrefSources: prefs.js
Profile1IncompatibleExtensions:
 Japanese Language Pack - <email address hidden>
 English (South Africa) Language Pack - <email address hidden>
 English (GB) Language Pack - <email address hidden>
 Default - {972ce4c6-7e08-4474-a285-3208198ce6fd}
Profile1PrefSources: prefs.js
Profiles:
 Profile0 - LastVersion=35.0.1/20150125222008 (In use)
 Profile1 - LastVersion=35.0.1/20150125222008
 Profile2 (Default) - LastVersion=35.0.1/20150125222008 (In use)
RelatedPackageVersions:
 rhythmbox-mozilla 3.0.2-0ubuntu2
 totem-mozilla 3.10.1-1ubuntu4
RunningIncompatibleAddons: True
SourcePackage: firefox
SubmittedCrashIDs:
 bp-39cb68f1-0f39-471b-863a-879bb2140901
 bp-70dc89dd-e04c-4c06-a92b-04dd92140513
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/09/2013
dmi.bios.vendor: LENOVO
dmi.bios.version: G2ET95WW (2.55 )
dmi.board.asset.tag: Not Available
dmi.board.name: 2306CTO
dmi.board.vendor: LENOVO
dmi.board.version: 0B98405 Std
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvrG2ET95WW(2.55):bd07/09/2013:svnLENOVO:pn2306CTO:pvrThinkPadX230:rvnLENOVO:rn2306CTO:rvr0B98405Std:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 2306CTO
dmi.product.version: ThinkPad X230
dmi.sys.vendor: LENOVO

[Launchpad Janitor (janitor)]

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

[avdd (avdd)]

Still a problem!

[avdd (avdd)]

Still here!

44.0.2+build1-0ubuntu0.14.04.1

[Donald Pellegrino (donald-a-pellegrino)]

I am able to reproduce this issue by opening file://usr/share/doc/python/FAQ.html when running Firefox in Safe Mode. However, I did not get the warning when opening about:blank.

$ dpkg-query --status firefox
Package: firefox
Status: install ok installed
Maintainer: Ubuntu Mozilla Team <email address hidden>
Architecture: amd64
Version: 47.0+build3-0ubuntu0.16.04.1
Xul-Appid: {ec8030f7-c20a-464f-9b0e-13a3a9e97384}

$ lsb_release -a
Description: Ubuntu 16.04.1 LTS

[Tian Yong (htian)]

Disable the extension 'Ubuntu Modifications' in Firefox solve this issue.