Problem

The following error is returned in the Javascript console when using TestTrack Pro Web in Google Chrome with the Adblock Plus extension installed:

‘Uncaught TypeError: Cannot read property 'length' of null’

Cause

Adblock Plus injects a stylesheet in the TestTrack Pro web page. TestTrack Pro attempts to access properties with null values when loading the page, but the null property values in the Adblock Plus stylesheet are not handled.

Solution

Add the domain that hosts TestTrack Pro Web to the Adblock Plus whitelist. Refer to the Adblock Plus documentation for more information.