Please help us help you and fill where relevant:
Your LimeSurvey version: 2 instances, 3.28.48+230207 and 5.6.2+230125
Own server or LimeSurvey hosting: self-hosted instances
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Hello @all,

I wanted to add 2FA to my CE installations, following the instructions in the manual .
Sadly, I came out way more confused than before and kindly ask for your advice.

• The link to the 2FA CE plugin in the manual gives me a 404. As does the link to the "Premium account".
• In LimeStore, the 2FA Plugin by Ahmed Galadima is only available to users who buy the Premium package - I assume this would be the plugin that the manual would have linked me to; I've noticed that it's only compatible with versions 3.x and 4.x though?
• As I've been paying for a 12-month-ComfortUpdate for over 7 years now I'm not sure what the "Premium account" would be if not that very subscription - I'm unable to obtain the plugin and am regularly taken back to the "buy a Premium account"-page.

My questions to you:

1. Is there a 2FA plugin compatible with e.g. the Microsoft Authenticator app that I can use both on a 3.28 LTS and a current version 5.x when self-hosting?
2. If so, do I need to buy a separate account/package for that? (note: I still need to self-host)
3. Is there a possibility to use a Yubikey instead of TOTP password apps for CE/self-hosted instance logins?

Thank you very much in advance.

Best,
Chris