If you see a message in Topbar saying:
"Update required: Click here to start" but nothing happens when you click on start you will have to restart Topbar manually. This seems to happen in some rare cases and we will work on a patch but as a workaround please right click on the Topbar icon in your system tray and close Topbar.
Open the system tray:
Right click the Topbar icon:
Click on "Close" to shut down Topbar:
Then start Topbar again by double clicking the Topbar icon on your desktop.
This will apply the update.