I am working through The Wikipedia Adventure with some of my students, and noticed that in Mission 1, there is a part of it - Your turn - that seems to stop working. I got to the pop-up when it asks me to us Edit source (I do not have an option for Create source as it asks) and click it, but then nothing happens. It does not progress or ask me to do anything else next.

Can you please help or give me direction for things to try?

This is the message where it stalls:

Your turn!

Creating your userpage on Wikipedia is as simple as editing it.
Click CREATE SOURCE or EDIT SOURCE above.
(This adventure always uses the SOURCE editor).