Change from Reply to Reply All or vice versa
Idea shared by Adam Lewis - July 10 at 5:40 AM
Proposed
It would be nice if there were a way to switch from a standard "Reply" to a "Reply All" after composing the message. Often times I change my mind about who I want to reply to but have to either manually add emails back in, more emails, or open a new message and copy and paste my response. Gmail offers this - 
 

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