Bug description
This happens when the script tries to take screenshots of the icons in #822.
We encounter an error of:
Message: [Exception... "Failure" nsresult: "0x80004005 (NS_ERROR_FAILURE)" location: "JS frame :: chrome://remote/content/marionette/capture.js :: capture.canvas :: line 141" data: no]
Possible fixes or solutions
There seems to be something wrong with the screenshotting functionality of Selenium. We should double check that the element is screenshotable.
Additional information
Could be an issue that has been fixed by more up-to-date versions of Selenium.