Chromium appears to stay on top of other applications even when it is not

[Aren Cambre]

(This may be related to but not the same as 1030060 and 1173234.)

Chromium stays on top of other applications, even when it shouldn't be drawn on the screen at all.

For example, if I minimize Chromium, it is still drawn as if it's on top of other applicaitons. Even though I cannot see these other applicaitons or parts thereof that were behind Chromium, I can interact with them with the mouse as if they are on top and in focus.

Also, even if Chromium is not minimized, it is still drawn above other applications even if another application gets the focus due to me interacting with it.

I can reproduce this on both a fresh install of Ubuntu 14.04 and an install of Xubuntu that started with 12.10 and has successively been upgraded through every release.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: chromium-browser 34.0.1847.116-0ubuntu2
ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9
Uname: Linux 3.13.0-24-generic x86_64
ApportVersion: 2.14.1-0ubuntu3
Architecture: amd64
CurrentDesktop: Unity
Date: Tue Apr 22 09:57:40 2014
Desktop-Session:
 DESKTOP_SESSION = ubuntu
 XDG_CONFIG_DIRS = /etc/xdg/xdg-ubuntu:/usr/share/upstart/xdg:/etc/xdg
 XDG_DATA_DIRS = /usr/share/ubuntu:/usr/share/gnome:/usr/local/share/:/usr/share/
DetectedPlugins:

Env:
 MOZ_PLUGIN_PATH = None
 LD_LIBRARY_PATH = None
InstallationDate: Installed on 2014-04-22 (0 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
SourcePackage: chromium-browser
UpgradeStatus: No upgrade log present (probably fresh install)
chromium-default: CHROMIUM_FLAGS=""
gconf-keys: /desktop/gnome/applications/browser/exec = b''/desktop/gnome/url-handlers/https/command = b''/desktop/gnome/url-handlers/https/enabled = b''/desktop/gnome/url-handlers/http/command = b''/desktop/gnome/url-handlers/http/enabled = b''/desktop/gnome/session/required_components/windowmanager = b''/apps/metacity/general/compositing_manager = b''/desktop/gnome/interface/icon_theme = b''/desktop/gnome/interface/gtk_theme = b''
modified.conffile..etc.default.chromium.browser: [deleted]

[Aren Cambre (aren-arencambre)]

Even if the lock screen appears because I didn't interact with Ubuntu for a while, the Chromium window still appears on top. I cannot interact with Chromium, but the window is still drawn on top of everything.

[Aren Cambre (aren-arencambre)]

This is weird: when Chromium is in front of the lock screen (per #2 above), it's still updating. If I have gmail open, the window keeps updating with new emails, chats, etc. as they come in, but I cannot interact with it. This seems like a possible information disclosure vulnerability as a lock screen is intended to maintain privacy.

[Aren Cambre (aren-arencambre)]

Another observation: if I have multiple Chromium windows, I cannot interact with a lower window unless I do something that causes the window to move or resize. Simply clicking on the window doe snot cause it to respond to anything, nor does it cause it to rise to the top of the screen.

[Aren Cambre (aren-arencambre)]

Correction on #4: looks like I can interact with Chromium windows that aren't on top, but only if I click on an area of the window that isn't covered up by another browser. Bear with me: For example, suppose I have three Chromium browser windows open with #1 in the front and #3 in the back, and each sticks out about 1" past each other on the right. If I click on the scrollbar of #3, I can interact with it. Technically that brings #3 to the top even though it's not being drawn that way. #2 is still visible, but if I click on anything on #2, I am in fact messing with browser #3 as it's on top in every respect except for being drawn on top by the UI.

I cannot get browser window #3 to be drawn on top by the UI unless I do something that causes the window to move or resize.

[Aren Cambre (aren-arencambre)]

I saw http://askubuntu.com/questions/453475/chromium-display-is-remanent-since-14-04-upgrade-with-gpu-acceleration-enabled and noticed how he got better results when using the --disable-gpu option. Indeed, that appears to make Chromium not stay on top.

I've attached console errors and warnings I get with and without that switch enabled. You'll see a ton of errors and warnings in the one without --disable-gpu.

In case it matters, I am running Ubuntu as a VirtualBox guest under Windows 8.1 x64. I'm on VirtualBox 4.3.10 and am using the current Guest Additions.

[Aren Cambre (aren-arencambre)]

I solved by unchecking "Enable 3D Acceleration" in my virtual machine's display settings. But there still appears to be a bug here that wasn't present before 14.04.

[Launchpad Janitor (janitor)]

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

[stavros daliakopoulos (stavrosd)]

Exactly the same problem with my system.

ProblemType: Bug
DistroRelease: upgraded from Lubuntu 13.10 to 14.04
Package: chrome-stable version 34 AND chrome-beta version 35
Graphics: Nvidia-closed source
CurrentDesktop: Lubuntu

In my intel machine chrome works as usual.

[Aren Cambre (aren-arencambre)]

I should update that unchecking "Enable 3D Acceleration" does not reliably fix. However, running Chromium using "chromium-browser --disable-gpu" does fix it, albeit making Chromium run noticably slowly.

Also reference http://askubuntu.com/questions/453475/chromium-display-is-remanent-since-14-04-upgrade-with-gpu-acceleration-enabled/

[q4a (q4a)]

I have the same problem, but i's not only chrome or chromium. Same problem with steam.
May be problem between 14.04 and Nvidia-closed source drivers?
ProblemType: Bug
DistroRelease: upgraded from Lubuntu 13.10 to 14.04
Package: chrome-stable 35 and steam
Graphics: Nvidia-closed source
CurrentDesktop: Lubuntu

[q4a (q4a)]

I think this bug is related to: https://bugs.launchpad.net/ubuntu/+source/nvidia-graphics-drivers-331/+bug/1326760

[vak (khamenya)]

not only with Nvidia. Here is with built in GPU:
VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)

Chrom Version 52.0.2743.116 (64-bit)
Ubuntu 16.10

[Paul White (paulw2u)]

We are sorry that we do not always have the capacity to review all reported bugs in a timely manner. However, there have been no comments on this bug report for several years.

This release of Ubuntu (14.04 or Trusty) is no longer receiving maintenance updates. If this is still an issue using a maintained version of Ubuntu please let us know otherwise this report can be left to expire in approximately 60 days time.

Paul White
[Ubuntu Bug Squad]

[Launchpad Janitor (janitor)]

[Expired for chromium-browser (Ubuntu) because there has been no activity for 60 days.]