Is there a way to create a "search folder" that compares header values between emails in separate folders?
In other words, is there a way to create a "search folder" that filters emails in one folder that have In-Reply-To header values containing only Message-ID header values in emails in another folder?
For example, I have an email in my Inbox folder with Message-ID "foo", and I have an email in my Sent folder with In-Reply-To "foo". Can I create a "search folder" containing both emails that matches the two header values without specifying "foo"? This match would omit an email in my Sent folder with In-Reply-To "bar".
In other words, is there a way to create a "search folder" that filters emails in one folder that have In-Reply-To header values containing only Message-ID header values in emails in another folder?
For example, I have an email in my Inbox folder with Message-ID "foo", and I have an email in my Sent folder with In-Reply-To "foo". Can I create a "search folder" containing both emails that matches the two header values without specifying "foo"? This match would omit an email in my Sent folder with In-Reply-To "bar".
Alla svar (1)
In short, no, because there doesn't seem to be any way for a filter to look at two messages concurrently.