I’m a very experienced programmer, but I have attempted to use Mailspring’s API and sample plugin and haven’t even gotten anything at all to work.
Before I delve deeper into this madness, I’d like to ask: Is it even possible to create a plugin that does the following:
When opening the “Reply” window.
Automatically takes the email’s “X-Original-To:” (if exists) or “To:” (fallback) header field.
Uses that as the “From:” of your new email.
The purpose is to add Email Alias support to Mailspring, so that people can click “Reply” and be sure that it will be sent as your alias, rather than exposing your true, internal mailbox.
People have asked for this feature in the past:
If plugins can achieve this, technically, then I’d like to code it.
I am not sure, of this is possible with a plugin. But maybe you want to implement it directly in the mailspring source code. The project is always open for pull requests.