Google plus addressing format and the unanswerable question

Google supports something called plus addressing, which is just username+alias@gmail.com or username+alias@example.com if you are signed up for their domains product.<p>The alias&#x2F;plus addressing is not exclusive to google. I have searched, posted on forums, asked around, and no one can seem to find a way to search gmail, or to create a filter that can locate all plus addressed emails.<p>As an example address: user+amazon.com@gmail.com<p>If I forget to add a filter for user+amazon.com, and really who has time to set that up right on the spot. Further, gmail doesn&#x27;t exactly show you must of the recipient address other than &quot;me&quot; unless you dig deeper into each email.<p>I want to be able create a filter that says if any To: address has a plus in it, mark it with a label.<p>I have tried regex, which I don&#x27;t, believe is supported. I have tried what I thought should work, as just to: user+ for which it finds all my email. And finally I have tried to just search To:+ and To:&quot;+&quot; as well as other variations.<p>Any suggestions, a plug in, anything?<p>Thank you.