Installing Gnome Shell Extensions
1 Install Firefox Add On
Select “Click here to install browser extension, and then click Allow on the pop-up notification. Finally, click Add in the pop-up marked ‘Gnome Shell integration’. The addon will install automatically. Minimise Firefox for now.
2 Install host connector
The website also requires a small program in order to offer the correct extension for your version of Gnome Shell. Click Activities at the top left of your screen and then type Terminal in the search bar at the top. Double-click the Terminal icon. Then type sudo apt-get install chrome-gnome-shell . Choose Y to confirm the installation.
3 Install Extensions
Return to your browser and reload the page https://extensions.gnome.org. Run a search for your extension of choice or scroll the lists. If you find one you like, click it and then select the rocker switch marked Off to install it. The system will ask if you’re sure that you want to install the extension. Click Install to continue.