Is it possible to use full Handlebars Markup Language (like Handlebars helpers, #each, #lookup, and callbacks to controllers) in Lightning email templates?
I want to create an email template for use by the user in the Activity Email panel. It needs to be able to look up names of records linked via junction objects. (I asked this recently with no responses.)
It has been 1 year since HML was deployed for email templates in Salesforce, but there is almost no information beyond simply picking a field from the main object.
The closest things I found were:
Create a hidden field and store info there, to pull into normal lightning template merge field