Can't "save and open" imported lesson

Hi, on firefox, just tried to import a new lesson, as I do every day, and nothing is happening, no error message, no red writing, nothing. I’ve refreshed the page to no avail. Any ideas?

@maths - I don’t seem to be having any problems importing in Firefox, either with the Import Lesson page or the Import Bookmarklet. Can you try importing the lesson again to see if it works?