Shoutbox

You can continue using Zero-G since there is a solution for both things you want. To hide the tabs, open your Messenger settings and go to the 7th tab (I use the Greek version of Messenger so I cannot be sure of what the tab is called, probably "Tabs" though) and tick the option below the box containing the tabs used in Messenger. This will hide the tabs. Now to hide the adverts, go here, download and run the file and the adverts will be gone!