Comment 155 for bug 357864

I still think that the current UI for this is wrong because it's disjunct/dislocated.
If we allow to edit the currently selected sender, then the control to start that should be near that sender. Clicking at the low end of a dropdown to edit the current entry at the top is bad UX imo.
Also, there's a scalability problem for users having many pre-defined accounts and identities. That command to edit the sender might end up as the 50th entry, requiring scrolling to see it and other such nuisance.
Just never put action commands to the end of a potentially unlimited list of things. We've tried that before (TB Tags list), and it never works. That's basic UX principles, really.