Emerald - Double Click To Maximise Window
By default, Emerald will fold a window up into the titlebar when you double click the titlebar. It calls this action "Shade". I came from Ubuntu 16.04 and am used to double-clicking the title bar to maximise the window. Luckily we can change the behaviour to do this.
System > Preferences > Look and Feel > Emerald Theme Manager
Then in the window, go to the settings tab and change the Titlebar Double-Click Action to Maximise/Restore