Github for Chollet's DL Jupyter Notebook code

I was running the code on a few days ago and now I am unable to run it. I am not able to select the code blocks, and CTRL+Enter does not work.

I am running it from a Fedora Linux box in Oracle Virtual Box. Again, it was fine a couple days ago. I have restarted the virtual machine and my laptop (Windows) a few times.

Thanks for any help you can provide.