QR code issued by ./manage.py add-admin is solid black square on Focal

[zenmonkeykstop]

Description

A QR code is generated when a user is created via the app server CLI, to simplify 2FA setup. On Focal, it currently shows as a solid black square

Steps to Reproduce

• on a Focal install:
• og in to the application server (ssh app if prod) and run the following:

  sudo -u www-data bash
  cd /var/www/securedrop
  ./manage.py add-admin
  

Follow the prompts to add a user, choosing N to the Yubikey question.

Expected Behavior

A QR code is displayed with the 2FA secret info for the new account.

Actual Behavior

A solid black square is displayed.

Comments

The text shared secret still works and the account can log in.
Suggestions to fix, any other relevant information.