"a statement, action, or incident regarded as an instance of indirect, subtle, or unintentional discrimination against members of a marginalized group such as a racial or ethnic minority"
That is consistent with the definition I had in mind when I wrote my comment. I do think trying to document unintended offenses is a bad idea. The recipient of the microagression should instead learn not to dwell on minor slights, ignore them, and/or assume good intent instead. It seems very toxic to live as if the people you talk to are secretly hurting you. Better to think of them as nice people with different methods of communication until they prove otherwise.