It turns out that Facebook allows you to log in with two variations of your password…

Interesting: It turns out that Facebook allows you to log in with two variations of your password: One with the first letter capitalized (because so many mobile phones automatically capitalize the first letter of a field to “help” you) and one with all the capitals/lowercase flipped (so that you can still log in with CAPS LOCK on).

Facebook passwords are not case sensitive (update) | ZDNet

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