By default the Gnome Shell user menu doesn’t show ‘Power Off’ option. Instead, user need holding the ‘Alt’ key to make the menu show it.

Here’s an entension for Gnome Shell > 3.2 that adds ‘Power Off’ to its user menu.

1. Download the extension poweroptions.tar.gz from this page

2. Put it under $HOME/.local/share/gnome-shell/extensions/ (create it if not exist), then extract the package. Read the README file for installation and more.

3. You can check your gnome-shell version by this command:

gnome-shell --version

Then, edit the “metadata.json” file and change the “shell version”

4. Restart gnome-shell by Alt+F2 and run r, or log out and back in.

5. Enable this extension in Advance Settings (gnome-tweak-tool), or execute:

gnome-shell-extension-tool -e