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I'm looking to create a filter in Gmail that will take any email with a certain
X-OriginatorOrg header value (e.g.,
example.com) and move it to a certain label. I've looked at the advanced search operators list on Google's help pages, but I can't seem to find anything that will enable me to search any value in the message headers, even if Gmail hasn't specifically created a search operator for it.
Is this at all possible with Gmail? If not, is there a third-party Gmail app in existence that offers this functionality?