Arduino board connected to USB port.
1) Launch duino.app.
2) Set Arduino board type.
3) Connect (pair) serial port.
4) Create new code project and enter code.
5) Attempt to compile and upload code, but "Serial Device Selected" is marked in red.
6) Once again select and connect serial port even though still shown as paired.
7) Still cannot compile and upload with "Serial Device Selected" marked in red.
8) Refresh browser and then I can compile and upload successfully.
Conditions: