Operating system: Windows 7
Graphics card: GTX 1070
Short description of error
Area light size widget does not update the area light's actual width and height.
The width and height properties are not updated until you get your mouse near them, and the actual width and height of the light is not updated until you then change the width and height another way, such as selecting the width or height parameter and pressing enter.
Changing the size other ways works just fine.
Exact steps for others to reproduce the error
Add an area light and use its size widget.