Setup Instructions for ProtonMail's Two Factor Authentication (2FA) using Yubikey 5

Setup instructions for ProtonMail’s Two-Factor Authentication using Yubico’s Yubikey 5 NFC along with the Yubico Authenticator application on an Android/iPhone devices. I have also added the instruction for setting up a spare key within this video description. Below you will find both the PDF written instructions for setting up Yubikey for ProtonMail and the how to create a spare key instructions.
PDF written instructions for Yubikey on Proton Mail:
www.dropbox.com/s/uvidsopx1vn...
Creating a spare Yubikey (backup) with Yubico Authenticator App:
1.) Before registering key #1 (see video instruction), take a photo of the QR code and for the
service you will be using (ProtonMail, Facebook, or etc) .Then email/download the photo
to a secure file on your computer.
2.) Register key #1 (enter the 6-digit code when requested)
3.) Using the photo you took earlier, scan the QR code with the Yubico Authenticator App.
Then scan key #2.
You will now be able to use both keys on that sight. (Note: this may not work with all services)

[@reaganheese8505]

Hey Old Guy Tech, it's Old Gal Ludite here. Even 2 1/2 years later, your little video came in very handy. Thanks for taking the time to make it!

[@fredrickcallahan4292]

Thanks Man. Even though PM has slightly changed their format your vid helped me complete what was becoming a brutal process.

[@yank3656]

thanks for sharing Old_Guy Tech

[@APrintmaker]

How do I add a second (backup) Yubikey? You did a great job with this tutorial, please consider doing more.

[@spacepathfinder1]

it is helpfull thank you.

[@theitzone01]

Thanks. Please clarify if it is possible to perform your ProtonMail 2Factor Authentication setup without involving the use of a cell phone? My goal is to only access ProtonMail from my desktop PC using my Yubikey without QR codes or a mobile phone getting into the picture. Is this possible? And will eliminating the Yubico Authenticator app and substituting it with the Yubico Manager app help me in only using my desktop PC?

[@tilde3904]

So what's the difference between this and the classic 2fa on authy or Google auth?

[@Fun_Dealer]

Hello, I followed this tutorial and everything worked fine. Then I came back to my protonmail a few months later and It will not let me login. The code my yubikey generates does not work. Any ideas?

[@marclussier9887]

Under settings, the 2fa line doesn't exist ?

[@ChristianLAdamo]

how I can recover my two factor if I lost my device ?? I have the recovery codes!

[@adrienberthier5440]

Didnt work