It shows and runs in the lock screen

[conualfy]

I think this is more likely a Gnome Shell bug, but I should also write it here. When the screen is locked, nothing should be available. But I see the bar and I can start applications from it, even though I cannot see them running, but when I unlock, I can see them. This is a huge security risk and should be fixed asap in Gnome.

[micheleg]

Hi, this is the common behaviour when "anything" goes wrong. The extension fails to disable itself when you lock the screen. This is typically due to some incompatibility with other extensions. I recommend you to

1. Install the latest version (v63). It's still not accepted on the extension website so you'll have to install it manually, e.g. https://micheleg.github.io/dash-to-dock/releases.html

2. If this doesn't help, It is known that on ubuntu uninstalling ubuntu-dock might fix the issue, although this is more a workaround than a clean solution. You might want to try this.

[MilyMilo]

Hey, I can say this in fact exist even with dash-to-dock v63.
It's quite tricky, since it only appears from time to time, either there's a dock in the login screen or I have a duplicated (vanilla settings) dock on the left while my one is also visible on the bottom.
A temporary fix is to restart gnome-shell with alt+f2 then r and enter.

[irakliy01]

I have the same issue. Moreover, after rebooting or locking screen I see two bars. As I remember, this bug was in 17.10 too.
Screenshot

[conualfy]

@micheleg I run version 63 already. The Ubuntu one is not active due to some incompatibility. Anyways, my idea is that Gnome should never allow anything but the safe things on the lock screen, the simplest way is to cover with a locked layer that covers everything else and blocks creating some other windows on top of that. I have reported it to Gnome, but they said it is the extension's problem, not Gnome's fault and closed my report. :(
https://gitlab.gnome.org/GNOME/gnome-shell/issues/237

[ywwg]

I see this problem in ubuntu 18.04 too.
I can't uninstall the ubuntu dock without removing the ubuntu desktop metapackage. (Mine is also disabled anyway)

[SMadani]

This happens to me every time on Ubuntu 18.04

[frommeyerc]

Happens here as well. Fresh updated Ubuntu 18.04. After deactivating dash-to-dock the issue is gone. I don't think flagging this as invalid helps a lot. Even if the bug would be better fixed somewhere else - as long as this is not done this (potentially) screws security. For me it breaks the whole extension.

[d2a-raudenaerde]

Still happens. Just upgraded from 16.04 to 18.04.

[Mbuntu]

@micheleg Youre first method ("Install the latest version (v63). It's still not accepted on the extension website so you'll have to install it manually, e.g. https://micheleg.github.io/dash-to-dock/releases.html") is worked for me. Thank you very much. :)

[micheleg]

@Mbuntu v63 should be available on the extension website, what do you mean by "It's still not accepted "?

[osilkin98]

I posted about this issue (#796) occurring in version 63

Install the latest version (v63). It's still not accepted on the extension website so you'll have to install it manually, e.g. https://micheleg.github.io/dash-to-dock/releases.html

[osilkin98]

I'm still having this issue. On multiple devices. All after fresh Ubuntu 18.04 installs.

Maybe @micheleg should do a better job of looking into issue tickets.

[conualfy]

I still experience the bug, too. Never saw any difference in this domain. Just logged out, moved the cursor to see the locked screen and started Terminal from my left bar.

[MagnetoOptical]

All of these comments seem to have Ubuntu in common. Indeed, when I'm running Fedora, I don't have this issue, but Ubuntu 17.10+ does produce the issue reliably.

It's a hack and it's not clean, but I have found the following works:

1. Install Dash to Dock
2. Disable Dash to Dock
3. Disable Ubuntu Dock (may already be disabled)
4. sudo apt remove gnome-shell-extension-ubuntu-dock (this will remove ubuntu-desktop metapackage as well)
5. Re-enable Dash to Dock
6. Enjoy until the next upgrade.

The issue seems to be specifically how Ubuntu is deploying their dock.

[conualfy]

All of these comments seem to have Ubuntu in common. Indeed, when I'm running Fedora, I don't have this issue, but Ubuntu 17.10+ does produce the issue reliably.

It's a hack and it's not clean, but I have found the following works:

1. Install Dash to Dock

2. Disable Dash to Dock

3. Disable Ubuntu Dock (may already be disabled)

4. sudo apt remove gnome-shell-extension-ubuntu-dock (this will remove ubuntu-desktop metapackage as well)

5. Re-enable Dash to Dock

6. Enjoy until the next upgrade.

The issue seems to be specifically how Ubuntu is deploying their dock.

How did you do that? I just tried and it wants to uninstall Ubuntu Desktop.
Later edit: you already said that. I am not sure what Ubuntu Desktop is, but if it is the Desktop, I want it, so cannot remove the package.

The following packages will be REMOVED:
  gnome-shell-extension-ubuntu-dock ubuntu-desktop

[osilkin98]

@ProfElectric Yeah, I believe I mentioned that in one of my issues, it's definitely an issue with Canonical's fork of Gnome. I've experimented with normal Gnome and didn't really have an issue.

[osilkin98]

@conualfy

Later edit: you already said that. I am not sure what Ubuntu Desktop is, but if it is the Desktop, I want it, so cannot remove the package

It's not the desktop but rather a list of packages that it states must be installed as its dependencies. Since the default gnome-shell-extension-ubuntu-dock is one of the packages within the dependencies, asking apt to remove it will also cause it to remove the list of dependencies that must be installed with ubuntu-desktop, but not the software in the list.

In other words, if you think of the ubuntu-desktop as being a condition that is satisfied when all the packages within its list are installed, if you remove a package within the list, the condition is no longer true, and so apt removes it as well.

There's a lot of documentation about meta-packages in Ubuntu, so hopefully this will clear things up.

[brianc118]

Experiencing this as well on a fresh 18.04 install

[Ads20000]

This seems to be a duplicate of #649 and #641. The Ubuntu bug is here, please mark yourself as affected by it and pay attention to when developers ask for more information so that they can fix the bug (here's my journal log when reproducing the bug)!

[mike10004]

I noted the following over at the Launchpad report: Open /usr/share/gnome-shell/extensions/ubuntu-dock@ubuntu.com/extension.js and somewhere around line 31, change

dockManager.destroy()

to

if (dockManager != null) {
    dockManager.destroy();
}

and the dock will stop appearing on the lock screen.

[pdrd]

if (dockManager != null) {
    dockManager.destroy();
}

@mike10004 Can confirm this solves the issue on Ubuntu 18.04.1 LTS. Personally i prefer the modification, because i'm working on a multi-user-workstation, where i am not able to uninstall the default packages.

[mike10004]

If I understand what's going on correctly, dockManager is declared globally, so it might still be an issue that Ubuntu Dock and Dash To Dock each construct a dock manager instance, but destroy() only gets called on one of them. A complete resolution would need each extension to retain a reference to the instance it creates.

[pdrd]

@mike10004 I understand your thoughts, but i took a look at the source code of dash-to-dock and gnome-shell-extension-ubuntu-dock and the dockManager variables in the extension.js files are file-local and conditionally set to new Docking.DockManager();.

What may be the problem is that in the gnome-shell-extension-ubuntu-dock/tree/extension.js enable() function the dockManager is initialized with null and the scenario i can imagine is that the enable() and disable() extension hooks are getting called by the extension system even if the ubuntu dock extension is not visible, cause otherwise your fix would take no effect. It seems that in our case the condition to set the local dockManager instance evaluates to false and the disable() call throws a typical uncatched TypeError.

@rugk I think it should be reported to the gnome-shell-extension-ubuntu-dock issue tracker and should not be addressed as dash-to-dock issue. The referenced issue #829 contains an error stack trace, which should not be affected by the seems-to-work-fix of @mike10004, so we might want to separate the issues?

[rugk]

I can actually reproduce this issue on non-Ubuntu distro(s), i.e. Fedora. See #829. As such it's likely not really related to Ubuntu – or there are multiple causes for that issue.

[pdrd]

That's quite interesting, because i'm working since two days on a ubuntu workstation with the fix, where i'm repeatedly locking/unlocking and the issue didn't came back since then - beforehand it was easily reproduceable. Might be multiple causes..

[furqaaaan]

I found a workaround for this that works for me. After customizing however i want using dash to dock, simply disable it. The settings will persist. No more having two docks or docks appearing at lockscreen

[micheleg]

Closing as duplicate of #641.