When I'm on fullscreen and create a new tab I can't type
When I'm on fullscreen and I hit ctrl+T to create a new tab I can't type to the urlbar.
If I press Ctrl+T in Full Screen mode then the Navigation Toolbar get visible if it is hidden and the location bar has focus and I can type immediately in the urlbar.
What happens in your case ?
Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.
- switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
- do NOT click the "Refresh Firefox" button on the Safe Mode start window