shotgunsoftware/tk-multi-launchapp — pull request #16 by manneohrstrom (2014-11-09 00:07:12+00:00)
Title: #27083 Adds setting which hides icons if application is not installed

Currently, there will be a "Launch Houdini" option in Shotgun and the shell (and a Houdini icon in the desktop) even if you haven't got Houdini installed.
This seems counter intuitive and this simple addition is trying to address that. It adds a small check to see if the DCC that is about to be launched actually exists. If not, the launch command (icon) is never registered with the engine, and will therefore not be visible to the user.

The behaviour is controlled by a preference, which defaults to the current behaviour, meaning that the upgrade is backwards compatible.
Turning off this logic is necessary in cases where you don't have an absolute path to the DCC and therefore cannot check it.