How to fix the interactive features of the Lumen textbook

The Lumen statistics textbook has numerous interactive “TRY IT” boxes that ask you questions so you can test yourself to see if you understand many of the concepts.  Every “TRY IT” box should have an interactive question like the one shown below.

But some browsers settings block the questions as shown here: 

If you only see the word “Loading” as shown above, that means the Lumen textbook isn’t working for you.  Fortunately, it is usually very easy to fix the “Loading”  problem.  Just open the same page in a different browser and that often works. Or try a “private window” in Firefox or try an “Incognito” window in Chrome.   Updating browsers can also fix the problem or allowing cookies and pop-ups for the Lumen website ( can also help.  The Lumen textbook is based on work done by Carnegie Mellon University and they have extensive instructions about how to fix this kind of display problem too, but it can take a lot of work to get a browser’s settings fixed and it is usually easier to just open the page in a different browser or in an incognito window.

Once you figure out what browser works, just keep using that same browser whenever you read the Lumen textbook.