Around October 2021, as a way to improve security on password account lockout, the brandable email template user_account_locked_email.xml was introduced. Custom labels such as $CONFIG.emailingLogoUrl$ work fine her, but the macro @TENANT_URL@ was not included for this template. If you need to add a password reset link or similar, then this would force you to hard code the Tenant URL, and also force you to brand different templates for each environment (Dev/Test/Prod).
If the macro @TENANT_URL@ gets added to the template, that would simplify branding by making possible to use a single branded file for several environments (the same customized template would work for Development , Testing and Production).
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