We've been telling people to put images using the included tool which hosts them on imgur and that they're supposed to be hosted there and safe from removal by the host.
I've seen that it isn't so, but I didn't at the time I didn't save links to particular questions and answers. Now I found this question of mine which, at least for me, has a missing picture and the direct link times out.
I've got the impression that the images uploaded to imgur should be saved for considerable time in order to be useful for some time after the question has been made. So what I want to know is how long that time is?