kevinrenskers/django-generic-mail — comment on commit 4152cc25614163dd4771672bda2f23675a98adff
File: generic_mail/templates/email/base_text_email.html line 1
By hvdklauw:

Here you also want a |safe escape.

Reasoning: It's text mail and you don't want any html tags to be escaped, they will be displayed as is.
vs <strong>