create.arduino.cc does not find my Arduino Uno, but Codebender finds it.

[kennethstevenson]

When I connect my Arduino Uno R3 with a USB cable the my Chromebook (Dell Latitude 5400), the webpage can't find my Arduino Uno R3. It has found it earlier.
If I copy/paste my code into https://edu.codebender.cc/class_demo, the same Arduino is found and the code is uploaded and the serial monitor returns information.

Any ideas?

Link to image of error message: https://drive.google.com/file/d/1-XmOZJYKfyYF_jsX1duYzW9GJus_rLXU/preview

Is codebender a better alternative than this site?