They talk about Google Authenticator syncing to your account, and you should disable that. Solid advice, but that'll leave you in shambles if you lose your phone.
To counter this, make a hard copy of the QR codes when you get them and store the hard copy somewhere. You can scan an old Auth QR, or you can scan it on a different phone. Just get an old android with only Authenticator, if you want a live backup.
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