For example taking myself as a poster on the jboss.org mailing lists, I'm using several identities, mostly because of "branding" requirement of different mailing lists.
In practice, sanne@redhat.com, sanne@hibernate.org, sanne@infinispan.org, sanne.grinovero@gmail.com and sgrinove@redhat.com are all me.
Sometimes we do need to cross-post so I don't know in advance which of the emails I've been using when mining for an older discussion.

For each of these, the faceting feature to search by poster in the search.jboss.org UI, just shows "Sanne Grinovero": the same label is listed multiple times, but when clicking on it I don't really know which one I'm selecting.

A useful improvement would be to either

• list the full email in the facet label (I guess trivial)
• consider all those emails as synonym terms, so that when I click on my email it matches any of my emails.

I think the second option is the most useful, at least if we stick to the assumption that noone is having the same name (which is kinda assumed already by the UI so I guess it's not too unpractical).