Issue
Salesforce will begin to require all users who log into Salesforce products to use Multi-Factor Authentication (MFA) on February 1, 2022. Will MFA be required to log into Salesforce and complete the Heroku Connect configuration?
Resolution
Yes, the integration user must log into Salesforce with MFA to complete the setup while MFA won't affect existing connections. Please also check this article, Will I need to reauthorize Heroku Connect after enabling MFA for Salesforce, for more details.