title: Emacs buffer copy with single stroke
body: <p>assume I have focus on BrokerSyncMasteredRecord.cc. I want to fast copy BrokerSyncMasteredRecord.cc to the left by one stroke(like some hotkeys). the final state in pic 2. Currently, I can only use C-x b and type in a few chars of the buffer name. this is very slow.</p>
  
  <p>NOTE: this should not be another opened replica buffer(e.g., BrokerSyncMasteredRecord.cc[replicated], you know what i mean if you are a emacs user) but exact the same buffer, just show in two different windows</p>