I had the same issue. Just to login to steam I had to downgrade my password to a less secure one that I could remember. It seems like Steam doesn't really want you to have secure passwords yet they claim that pasting your password is not secure. Even security blogs of the top security experts say to use a secure password manager, yet Steam thumbs their nose at you for using one. Steams policy makes things less secure because a great majority of people can't remember secure passwords so they will make one easy to remember which in turn makes it easy to crack. But it's not just Mac, it's every platform.

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