Enabling Khmer Unicode Keyboard on MacOS Sierra 10.12

You don't need to install anything on MacOS Sierra v10.12 or may be even on Mac OSX Mavericks v10.9. The Khmer Unicode keyboard layout and font (Kh Battambang) are built-in. It was created by Mr. Danh Hong (dnhhng@yahoo.com). To make it show up in the Menu bar, you have to open the Keyboard Preferences and add the keyboard named Khmer in the Input Sources as shown below.

Note that this keyboard layout does not work well with the Khmer fonts created by different developers. The issue can be missing or overlapping characters in Microsoft Offices. You have to use the fonts created by Mr. Danh Hong such as Kh Battambang (similar to Limon S1) and Kh Muol (similar to Limon R1).

Keyboard layout