Update Chrome:

1. Log in

2. At the bottom right, select time

3. Select Settings

4. Under "Google Chrome OS", you'll find which version of the Chrome operating system the Chromebook is using

5. Select Check for Updates

Check Screen Resolution:

1. While you are in settings, locate Display options

2. Display size needs to be set on the smaller side. Suggested size is 105%

Restart the Chromebook and try CDT again