For those working on Ubuntu Linux with multiple monitors, here’s how to enable the left dock panel and top bar on all displays.
GNOME by default will extend the desktop screen if you plugged in a second monitor. However, both the left (or bottom) dock panel and top bar do NOT appear in the non-primary displays. It shows only a blank desktop with background wallpaper.
For those want to show the panels on all monitors to make them look like the primary display, this tutorial may help!
1. Show the Dock Panel on All Displays:
The left (or bottom if you moved it) panel in Ubuntu is handled by Gnome extension (Dash-to-Dock). It has built-in option to toggle show dock on all displays. And users can enable it via the steps below.
UPDATE: Ubuntu has updated the ‘Appearance‘ settings dialog, so users may easily enable this feature via Settings -> Appearance -> Dock -> Show on ‘All Displays’.
Single command to display dock on all monitors:
Firstly, either press Ctrl+Alt+T key combination on keyboard, or search or and open terminal from activities overview screen.
When terminal opens, copy and paste the command below into the window and hit Enter:
gsettings set org.gnome.shell.extensions.dash-to-dock multi-monitor true
This command will enable the feature immediately!
Enable multi-monitors support via Dconf Editor:
For those hate Linux commands, the graphical configuration tool ‘Dconf Editor’ is present to toggle the settings.
Firstly, search for and install ‘Dconf Editor’ in Ubuntu Software if you don’t have it.
Then, launch the tool and navigate to ‘org/gnome/shell/extensions/dash-to-dock‘. Scroll down and you’ll find the toggle icon for ‘multi-monitor’ support.
2. Enable GNOME Top Bar on Multiple Monitors:
The Top bar is one of the core GNOME components. It does not provide option to toggle multi-monitor support. However, a third-party Gnome extension can do the trick!
For GNOME 38 and earlier:
For Ubuntu 21.04, Ubuntu 20.04, Debian 11 with GNOME 3.38 and earlier version, this open-source project adds ability to enable multi-monitor support.
1.) Firstly, open terminal by searching from the overview screen and run command to install the chrome-gnome-shell package:
sudo apt install chrome-gnome-shell
2.) Next, go to the extension web page and use the ON/OFF switch to install it:
For those don’t see the slider icon, click the ‘click here to install browser extension‘ link to install browser add-on and refresh the web page.
For GNOME 40+:
The extension does not support for Ubuntu 22.04 and Fedora 34+ with GNOME 40+ so far. Users may instead install this fork manually.
1.) First, search for and open terminal from the activities overview screen.
2.) When terminal opens, run command to get the source code:
git clone https://github.com/realh/multi-monitors-add-on.git
For those don’t have git, install it via sudo apt install git command.
3.) After cloning the source, navigate to the generated folder via cd command:
cd multi-monitors-add-on
And finally copy the extension to the place for single user only:
cp -r multi-monitors-add-on@spin83 ~/.local/share/gnome-shell/extensions/
UPDATE for Ubuntu 22.04 with GNOME 42, you also have to disable version validation by running command in terminal:
gsettings set org.gnome.shell disable-extension-version-validation true
4.) Finally, restart Gnome Shell either by log out and back in, or pressing Alt+F2, type r and hit Enter. And, use “Gnome Extensions” app to toggle on/off the extension as well as change its settings.
For those don't have "Gnome Extensions" app, install it viasudo apt install gnome-shell-extension-prefscommand for Ubuntu. Or runsudo dnf install gnome-extensions-appfor Fedora.