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src/components/structures/RoomView.js

@@ -501,6 +501,8 @@ module.exports = React.createClass({
         this._updateRoomMembers();
     },
 
+    // rate limited because a power level change will emit an event for every
+    // member in the room.
     _updateRoomMembers: new rate_limited_func(function() {
         // a member state changed in this room, refresh the tab complete list
         this.tabComplete.loadEntries(this.state.room);