Solved
I can add new applets to a chapter of an existing book, but when I try to edit a chapter or add a new chapter to a book I get a strange vertical bar, with no possibility of editing
chris
Files:
chapter.PNG
The same problem 
We've seen that a couple of times but have no idea how to reproduce/fix it (sorry!)
Does it work in an incognito tab?
hi Michael, what do you mean by an incognito tab?chris
it's fixed now!!chris
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