Changes are not saved when pressing "Fork this sketch"!

I spent some time playing with the code for one of the examples and decided that I was satisfied with the result I got and wouldn’t want to lose my work, so I pressed “Fork this sketch” to be able to save it. To my great surprise and sadness, every change I made was reset and I lost all my work. :frowning:

The same annoyance happens when you sign in for the first time.