Let me explain my situation.
I use UBUNTU 14 and it is regularly updated.
I downloaded the Arduino 1.6.6 compressed file from Arduino.cc for Linux.
I extracted it in the home folder.
I run Arduino by double clicking on the by default executable arduino file. Arduino launches and all is fine.
UBUNTU automatically shows a launch icon in the UNITY bar on the left. Every modern UBUNTU user knows this UNITY bar.
I lock the Launcher in the UNITY bar by right clicking on it and choosing "Lock to Launcher".
I close Arduino by choosing 'Quit' in the 'File' menu.
Then comes the unfortunate observation: When wanting to launch from the UNITY bar by clicking on the locked Arduino Launcher in the bar the Arduino splash shows and immediately disappears and nothing happens.
Bugger!
Why is that?
PS: No terminal tricks, did them all, none worked. Arduino launches from everywhere except from the UNITY bar having locked the presented icon after regular successful launch via directly double-clicking the executable Arduino file.