Why Firmata Test doesn't allow me to choose a port? I'm a beginner and, sorry, also I don't speak English very well. However, I'm going to try to explain my problem. 
I'm working on Ubuntu 14.04.2 and Arduino Uno R3. 
I downloaded Firmata Test binaries for Linux 64 bit, I gave it permissions with chmod 754 &lt;file&gt;. Also I uploaded StandardFirmata from Arduino IDE to the board. Afterwards, I quit Arduino IDE and ran Firmata Test with ./file. But, the Port menu has no items within. I tried restarting the board and the application as well.

What can I do?
I had the same problem until I ran it as:
sudo ./file