Remove unnecessary `btn` class

src/templates/chatroom_toolbar.html

@@ -1,6 +1,6 @@
 {[ if (o.use_emoji)  { ]}
 <li class="toggle-toolbar-menu toggle-smiley dropup">
-    <a class="btn toggle-smiley fa fa-smile-o" title="{{{o.label_insert_smiley}}}" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"></a> 
+    <a class="toggle-smiley fa fa-smile-o" title="{{{o.label_insert_smiley}}}" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"></a> 
     <div class="emoji-picker dropdown-menu toolbar-menu"></div>
 </li>
 {[ } ]}

src/templates/toolbar.html

@@ -1,6 +1,6 @@
 {[ if (o.use_emoji)  { ]}
 <li class="toggle-toolbar-menu toggle-smiley dropup">
-    <a class="btn toggle-smiley fa fa-smile-o" title="{{{o.tooltip_insert_smiley}}}" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"></a> 
+    <a class="toggle-smiley fa fa-smile-o" title="{{{o.tooltip_insert_smiley}}}" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"></a> 
     <div class="emoji-picker dropdown-menu toolbar-menu"></div>
 </li>
 {[ } ]}