This would be very useful for mass-forwarding / processing of Emails.
As it is primarily tasked with adding automatic filter actions / conditions, FiltaQuilla would need to implement a new menu item
"Forward with SmartTemplates" which would have to trigger smartTemplates, telling it which HTML file to use as template.
SmartTemplates will implement a listener on the background page so that it can get the command from FiltaQuilla to reply to a message with a certain template. The message header URI would have to be forwarded so that ST can identify the original message. It will then trigger a reply (through composer, because that's the only place ST can currently process mail), autopmatically open the email editer, process it as usual (e.g. setting a new recipient, from address, subject line etc.) and after completion automatically send off the message.
Corresponding FiltaQuilla issue: issue 153