yes i always backup my 2FA QR. by take a screenshot on it
because i usually try new ROM in my phone, sometimes bad things happen and i can't access my phone
i recommend you to backup when you set a new 2FA
So you use custom/rooted software to run your phone and keep screenshots of 2FA codes? That basically calls for an accident to happen!
yes i use custom ROM, but i don't use that phone to keep screenshot of QR codes
i use my computer to back it up and store it in encrypted folder
hope it safe there