         return @props.messages != next.messages or @props.user_map != next.user_map or @props.account_id != next.account_id
 
     list_messages: ->
-        is_next_message_sender = (index, list, map) ->
-            if index + 1 == list.length
+        is_next_message_sender = (index, dates, messages) ->
+            if index + 1 == dates.length
                 return false
-            current_message = map.get(list[index])
-            next_message = map.get(list[index + 1])
+            current_message = messages.get(dates[index])
+            next_message = messages.get(dates[index + 1])
             return current_message.get('sender_id') == next_message.get('sender_id')
 
-        is_prev_message_sender = (index, list, map) ->
+        is_prev_message_sender = (index, dates, messages) ->
             if index == 0
                 return false
-            current_message = map.get(list[index])
-            prev_message = map.get(list[index - 1])
+            current_message = messages.get(dates[index])
+            prev_message = messages.get(dates[index - 1])
             return current_message.get('sender_id') == prev_message.get('sender_id')
 
-        k = @props.messages.keySeq().sort(misc.cmp_Date).toJS()
+        sorted_dates = @props.messages.keySeq().sort(misc.cmp_Date).toJS()
         v = []
-        for date, i in k
+        for date, i in sorted_dates
             sender_account = @props.user_map.get(@props.messages.get(date).get('sender_id'))
             sender_name = sender_account.get('first_name') + ' ' + sender_account.get('last_name')
 

            e.preventDefault()
            mesg = @refs.input.getValue()
            # block sending empty messages
            if mesg.length? and mesg.length >= 1
                @props.redux.getActions(@props.name).send_chat(mesg)
                @clear_input()


        if @props.show_avatar
            marginBottom = "20px" # the default value actually..
        else
            marginBottom = "3px"

        if not @props.is_prev_sender and @sender_is_viewer()
            marginTop = "17px"

        if not @props.is_prev_sender and not @props.is_next_sender
            borderRadius = '19px 19px 19px 19px'
        else if not @props.is_prev_sender
            borderRadius = '19px 19px 5px 5px'
        else if not @props.is_next_sender
            borderRadius = '5px 5px 19px 19px'

        <Col key={1} xs={10} sm={9}>
            {@show_user_name() if not @props.is_prev_sender and not @sender_is_viewer()}
            <Panel style={background:color, wordWrap:"break-word", marginBottom: marginBottom, marginTop: marginTop, borderRadius: borderRadius}>
                <ListGroup fill>
                    <ListGroupItem style={background:color, fontSize: font_size, paddingBottom:'1px', borderRadius: borderRadius}>
                        <Markdown value={value}
                                  project_id={@props.project_id}
                                  file_path={@props.file_path} />
