Gnome-Window-Applets is a Gnome panel applets that substitute maximized window title and buttons.Window Title and Window Buttons are essentially controls for windows that are placed on the Panel instead of a window. By default they only control maximized windows, but can be configured to control any focused window.
Download and install Gnome-Window-Applets
Select to download appropriate deb package and double click to install:
Or download from gnome-look.org
Add applets to panel and hide the window decorations on maximized windows
Right click on gnome panel and select “Add to Panel”,in following screen add “Window Buttons”,”Window Title”,then choose a right position by right-clicking on them and select “Move”.