Configuring modules for email sending and formatting is a pain and confusing. Most mailing modules rely on Mailsystem module to help configure this.
In D7 Mailsystem 3.x there's an improved method of doing this by using a delegator class. https://www.drupal.org/project/mailsystem/issues/1508104. I propose that the class and related functions be put into core. The UI can stay out of core.
This will help any combo of modules share the responsibility of sending emails. One module can be used for formatting HTML (MimeMail, HTMLmail) and another for sending (SMTP, PHPMailer, Postmark, SendGrid, ...). The popular modules can then use the new class to allow other modules to share in the work and also provide a simple UI (without needing to install Mailsystem if they don't need that extra power).
Recent comments
We can no longer add contrib projects in the Tugboat sandboxes that we use for core PR's? Can this be fixed or is there a reason for this? We can add contrib projects to demo...
Apr 25th Weekly Meetings
The Mail System and MimeMail modules are now installed. I'll let you know if they solve the problem. Edit: Using Mail System with MimeMail I was able to send plain text emails. There is...
HTML Email treated as plain text
If you haven't already I recommend installing Mail System and MimeMail. The latter will help format emails as HTML and first helps with configuring which module will handle the formatting...
HTML Email treated as plain text