Converted tooltips to coffee too, and removed both converted files from the included js header.

lms/static/coffee/src/discussion/tooltips.coffee

+$ ->
+  new Tooltips
+
+class @Tooltips
+  constructor: () ->
+    @$body = $('body')
+    @$tooltip = $('<div class="tooltip"></div>')
+    @$body.delegate '[data-tooltip]',
+      'mouseover': @showTooltip,
+      'mousemove': @moveTooltip,
+      'mouseout': @hideTooltip,
+      'click': @hideTooltip
+
+  showTooltip: (e) =>
+    tooltipText = $(e.target).attr('data-tooltip')
+    @$tooltip.html(tooltipText)
+    @$body.append(@$tooltip)
+    $(e.target).children().css('pointer-events', 'none')
+
+    tooltipCoords =
+      x: e.pageX - (@$tooltip.outerWidth() / 2)
+      y: e.pageY - (@$tooltip.outerHeight() + 15)
+
+    @$tooltip.css
+    'left': tooltipCoords.x,
+    'top': tooltipCoords.y
+
+    @tooltipTimer = setTimeout ()=>
+      @$tooltip.show().css('opacity', 1)
+
+      @tooltipTimer = setTimeout ()=>
+        @hideTooltip()
+      , 3000
+    , 500
+
+  moveTooltip: (e) =>
+    tooltipCoords =
+      x: e.pageX - (@$tooltip.outerWidth() / 2)
+      y: e.pageY - (@$tooltip.outerHeight() + 15)
+
+    @$tooltip.css
+      'left': tooltipCoords.x
+      'top': tooltipCoords.y
+
+  hideTooltip: (e) =>
+    @$tooltip.hide().css('opacity', 0)
+    clearTimeout(@tooltipTimer)

lms/static/js/tooltips.js

-var $body;
-var $tooltip;
-var tooltipTimer;
-var tooltipCoords;
-$(document).ready(function() {
-    $body = $('body');
-    $tooltip = $('<div class="tooltip"></div>');
-    $body.delegate('[data-tooltip]', {
-        'mouseover': showTooltip,
-        'mousemove': moveTooltip,
-        'mouseout': hideTooltip,
-        'click': hideTooltip
-    });
-});
-
-function showTooltip(e) {
-    var tooltipText = $(this).attr('data-tooltip');
-    $tooltip.html(tooltipText);
-    $body.append($tooltip);
-    $(this).children().css('pointer-events', 'none');
-
-    tooltipCoords = {
-        x: e.pageX - ($tooltip.outerWidth() / 2),
-        y: e.pageY - ($tooltip.outerHeight() + 15)
-    };
-
-    $tooltip.css({
-        'left': tooltipCoords.x,
-        'top': tooltipCoords.y
-    });
-
-    tooltipTimer = setTimeout(function() {
-        $tooltip.show().css('opacity', 1);
-
-        tooltipTimer = setTimeout(function() {
-            hideTooltip();
-        }, 3000);
-    }, 500);
-}
-
-function moveTooltip(e) {
-    tooltipCoords = {
-        x: e.pageX - ($tooltip.outerWidth() / 2),
-        y: e.pageY - ($tooltip.outerHeight() + 15)
-    };
-
-    $tooltip.css({
-        'left': tooltipCoords.x,
-        'top': tooltipCoords.y
-    });
-}
-
-function hideTooltip(e) {
-    $tooltip.hide().css('opacity', 0);
-    clearTimeout(tooltipTimer);
-}

lms/templates/discussion/_js_head_dependencies.html

@@ -12,8 +12,6 @@
 <script type="text/javascript" src="${static.url('js/URI.min.js')}"></script>
 <script type="text/javascript" src="${static.url('js/vendor/underscore-min.js')}"></script>
 <script type="text/javascript" src="${static.url('js/vendor/backbone-min.js')}"></script>
-<script type="text/javascript" src="${static.url('js/tooltips.js')}"></script>
-<script type="text/javascript" src="${static.url('js/discussion-filter.js')}"></script>
 
 <link href="${static.url('css/vendor/jquery.tagsinput.css')}" rel="stylesheet" type="text/css">
 <link href="${static.url('css/vendor/jquery.autocomplete.css')}" rel="stylesheet" type="text/css">