soensWorks normally here on 2016.12. Not sure what you did to change the behavior but you might check you mouse settings. Maybe the left button is set to doubleclick with one click.
JohnThats a new feature in 2016.11. From the 2016.11 eZine.You can open a virtual instrument’s UI by clicking ona track header’s audio or MIDI icon, whether as aSimple Instrument or as tracks within a folder.