Rules (filtering on emails) - simultaneous access to emails

When I’m updating rules, it would be a real bonus if I could simultaneously access the email messages.
I’m sure you’ve wanted to do the same ?!
For example, I’ve a collection of emails in my top level inbox, and I want to add new rules for them all.
It’s clunky and tiresome, to have to close the rules popup window, in order to collect the next email address in order to update or create a new rule.