Sign in using QR code without master password

Guys, I hope to help the community.

What if we did this? @dh024 @Ben86 @vachan

I thought about that … Is it possible to adopt a temporary master password for Qrcode?
If going to public places it would make sense to have a qr code with a temporary master password. I could be right or wrong, but I would like to know your opinion.

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