Firefox won't automatically adjust the toolbar / tab and content size under high resolution environment in Ubuntu 14.04.1

[Po-Hsu Lin]

Steps to reproduce:

1. Install Ubuntu 14.04.1 + update + AMD video driver on a 3840x2160 high-resolution laptop
2. Boot to desktop with the highest resolution (3840x2160)
2. Open Firefox browser, ,make sure that it is on the latest version (34.0)

Actual results:

Toolbar / tab is too small, and the content size needs to be manually enlarged.

Expected results:

Toolbar / tab and the content size should be larger in this high resolution environment.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: firefox 34.0+build2-0ubuntu0.14.04.1
ProcVersionSignature: Ubuntu 3.13.0-43.72-generic 3.13.11.11
Uname: Linux 3.13.0-43-generic x86_64
AddonCompatCheckDisabled: False
ApportVersion: 2.14.1-0ubuntu3.6
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: ubuntu 1664 F.... pulseaudio
 /dev/snd/controlC1: ubuntu 1664 F.... pulseaudio
BuildID: 20141127111021
CRDA:
 country TW:
  (2402 - 2472 @ 40), (3, 27)
  (5270 - 5330 @ 40), (3, 17), DFS
  (5735 - 5815 @ 40), (3, 30)
Channel: Unavailable
CurrentDesktop: Unity
Date: Tue Jan 6 02:48:38 2015
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 2015-01-05 (0 days ago)
InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
IpRoute:
 default via 10.101.46.1 dev wlan0 proto static
 10.101.46.0/24 dev wlan0 proto kernel scope link src 10.101.46.53 metric 9
Locales: extensions.sqlite corrupt or missing
Plugins:
 iTunes Application Detector - /usr/lib/mozilla/plugins/librhythmbox-itms-detection-plugin.so (rhythmbox-mozilla)
 VLC Multimedia Plugin (compatible Videos 3.10.1) - /usr/lib/mozilla/plugins/libtotem-cone-plugin.so (totem-mozilla)
 DivX® Web Player - /usr/lib/mozilla/plugins/libtotem-mully-plugin.so (totem-mozilla)
 Windows Media Player Plug-in 10 (compatible; Videos) - /usr/lib/mozilla/plugins/libtotem-gmp-plugin.so (totem-mozilla)
 QuickTime Plug-in 7.6.6 - /usr/lib/mozilla/plugins/libtotem-narrowspace-plugin.so (totem-mozilla)
PrefSources: prefs.js
Profiles: Profile0 (Default) - LastVersion=34.0/20141127111021
RelatedPackageVersions:
 rhythmbox-mozilla 3.0.2-0ubuntu2
 totem-mozilla 3.10.1-1ubuntu4
RunningIncompatibleAddons: False
SourcePackage: firefox
Themes: extensions.sqlite corrupt or missing
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 11/19/2014
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A00
dmi.board.name: BBE4C1
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: Not Specified
dmi.modalias: dmi:bvnDellInc.:bvrA00:bd11/19/2014:svnDellInc.:pnInspiron7548:pvrA00:rvnDellInc.:rnBBE4C1:rvrA00:cvnDellInc.:ct8:cvrNotSpecified:
dmi.product.name: Inspiron 7548
dmi.product.version: A00
dmi.sys.vendor: Dell Inc.

[Cypressyew+bugzilla (cypressyew+bugzilla)]

Created attachment 8544402
Screenshot

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:34.0) Gecko/20100101 Firefox/34.0
Build ID: 20141127110711

Steps to reproduce:

1. Install Ubuntu 14.04.1 + update + AMD video driver on a 3840x2160 high-resolution laptop
2. Boot to desktop with the highest resolution (3840x2160)
2. Open Firefox browser, ,make sure that it is on the latest version (34.0)

Actual results:

Toolbar / tab is too small, and the content size needs to be manually enlarged.

Expected results:

Toolbar / tab and the content size should be larger in this high resolution environment.

[Gijskruitbosch+bugs (gijskruitbosch+bugs)]

*** This bug has been marked as a duplicate of bug 1081142 ***

[Launchpad Janitor (janitor)]

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

[Olivier Tilloy (osomon)]

This bug was marked as fixed upstream.

Po-Hsu Lin, can you confirm whether this now works as expected for you?

[Mario Vukelic (kreuzsakra)]

I am not the OP, but I have the same resolution, 3840x2160 on 15.6" display. Using Firefox 63 (as of today's update) on Cosmic, I still have to set layout.css.devPixelsPerPx to 2.5 in about:config for a usable Firefox. In both X and Wayland.