I bought an old Dell D430 laptop which is pretty old and small (12″) and I installed Lubuntu 14.04.02
The problem is that the fullscreen mode on Chromium and Chrome is not working as expected. It hides the application bar at the bottom but does not allow the browsers to go fullscreen – tabs and address bar are staying in their place when you press F11.
The problem is that the F11 key is taken from the system to make the current focused window fullscreen. You can see it here: https://help.ubuntu.com/community/Lubuntu/Keyboard
So just go to ~/.config/openbox , backup the lubuntu-rc.xml file and edit the original one replacing the F11 shortcut for toggle fullscreen with F10 for example.
Logout and login again and now when you press F11 in chrome or chromium it will go fullscreen, instead of using the default system shortcut.