How to hide top bar in Ubuntu 18.04?

First open the terminal and install chrome-gnome-shell package:

sudo apt install chrome-gnome-shell

Then install one of these extensions:

• GNOME Shell integration for Chrome

• GNOME Shell integration for Firefox

• GNOME Shell integration for Opera

Finally, head over to the GNOME Extensions page for the "Hide Top Bar" extension and enable the ON/OFF switch for the extension to install.

For reference, install gnome-tweaks and run:

sudo apt install gnome-shell-extension-autohidetopbar

Then log out and back in. The option to auto hide the top bar will be available from gnome-tweaks tool in the extensions section.

The simplest and working way I found is to install the Dash-to-Panel GNOME extension. Works like a charm.

Dash to Panel Extension

You can toggle it from the browser itself.

I was having the same problem about removing top bar. What I do is hack into the theme css, and edit it in place.

Edit /usr/share/gnome-shell/theme/ubuntu.css, add to the bottom

#panel, #panel * { 
    height: 0px; 
    color: rgba(0,0,0,0); 
} 

The top bar is there, but won't be visible and can't interact with user.

gnome-extensions command line

The snapification of browsers broke the chrome-gnome-shell method mentioned at https://askubuntu.com/a/1029905/52975 with error message:

Although GNOME Shell integration extension is running, native host connector is not detected

as mentioned at Although GNOME Shell integration extension is running, native host connector is not detected so if you don't want to find a non snapified browser, you can download the Zip manually from: https://extensions.gnome.org/extension/3906/remove-app-menu/ or:

wget https://extensions.gnome.org/extension-data/hidetopbarmathieu.bidon.ca.v97.shell-extension.zip

You can check your GNOME shell version as shown at: How do I check my version of GNOME-Shell? with either:

gnome-extensions version
gnome-shell --version

to determine which versions are compatible based on the extensions website. Then:

gnome-extensions install hidetopbarmathieu.bidon.ca.v97.shell-extension.zip
gnome-extensions enable [email protected]

As soon as you run enable, the top bar is immediately gone.

I wish we had a more decent standard single command CLI method, see: https://unix.stackexchange.com/questions/617288/command-line-tool-to-install-gnome-shell-extensions

Other extensions of interest:

• https://github.com/pixel-saver/pixel-saver worked on Ubuntu 21.10, but I think you have to log out and login again. But running this together with [email protected], I managed to remove both the top bar and the title bar on Ubuntu 21.10, effectively making all maximized windows become full screen! You can make them not-fullscreen with the default shortcut Alt + F10 if needed (since there's not title bar to click the unmaximize button on).
• https://github.com/franglais125/no-title-bar hides the title bar instead of the top bar

Related:

• Remove title-bar of all maximized windows in GNOME 3
• How to open windows directly in full screen mode on Ubuntu 18.04? asks how to remove both title bar and top bar

Tested on Ubuntu 21.10.