I was posting an answer to this question. Something strange happened that I do not understand (involving me clicking the go back button of my browser somehow) and now the answer appears TWICE under this question.
I've never seen anything like this happen before, and I have posted nearly one thousand SE questions. I've asked that the two answers not be deleted until at least someone can investigate.
In the mean time, I will manually copy/paste the answer text and post it under the actual target question.
Here is an ugly zoomed-out screenshot to document the end of one copy and the beginning of the next: