Speedgrader - Website URL submission with no preview

Community Member

In assignments, I frequently ask for screenshots to be taken and saved to their google drive. Using the shareable link, the students submit as a website URL.


When using speedgrader to grade these assignements: 

Sometimes I get a preview of the site like below:



But most often I get a black screen, forcing me to open in a new tab. Which makes the speedgrader a lot less speedy. 



Any idea why they aren't displaying a preview or how to submit differently so I always see a preview in speedgrader?