diff --git a/src/history.js b/src/history.js
index 4958af0..453fe53 100755
--- a/src/history.js
+++ b/src/history.js
@@ -1,194 +1,187 @@
 (function () {
-
-   var global = window;
-
-   var history_viewer, history_popup;
-
-   function getHistoryKeys() {
-      var keys = [];
-      for (var i = 0; i < localStorage.length; i++) {
-         var k = localStorage.key(i);
-         if (k.indexOf("hist_elem") == 0) {
-            keys.push(k);
-         }
-      }
-
-      keys.sort();
-      keys.reverse();
-      return keys;
-   }
-
-   function getHistory() {
-      var hist_items = [];
-      $.each(getHistoryKeys(), function (i, key) {
-         hist_items.push(JSON.parse(localStorage.getItem(key)));
-      });
-
-      return hist_items;
-   }
-
-   function getHistoricalServers() {
-      var servers = {};
-      $.each(getHistory(), function (i, h) {
-         servers[h.server] = 1;
-      });
-
-      var server_list = [];
-      for (var s in servers) server_list.push(s);
-
-      return server_list;
-   }
-
-   function populateHistElem(hist_elem) {
-      var s = hist_elem.method + " " + hist_elem.endpoint + "\n" + (hist_elem.data || "");
-      history_viewer.setValue(s);
-      history_viewer.clearSelection();
-   }
-
-   function applyHistElem(hist_elem) {
-      var session = sense.editor.getSession();
-      var pos = sense.editor.getCursorPosition();
-      var prefix = "";
-      var suffix = "\n";
-      if (sense.utils.isStartRequestRow(pos.row)) {
-         pos.column = 0;
-         suffix += "\n";
-      }
-      else if (sense.utils.isEndRequestRow(pos.row)) {
-         var line = session.getLine(pos.row);
-         pos.column = line.length;
-         prefix = "\n\n";
-      }
-      else if (sense.utils.isInBetweenRequestsRow(pos.row)) {
-         pos.column = 0;
-      }
-      else {
-         pos = sense.utils.nextRequestEnd(pos);
-         prefix = "\n\n";
-      }
-
-      var s = prefix + hist_elem.method + " " + hist_elem.endpoint;
-      if (hist_elem.data) s += "\n" + hist_elem.data;
-
-      s += suffix;
-
-      session.insert(pos, s);
-      sense.editor.clearSelection();
-      sense.editor.moveCursorTo(pos.row + prefix.length, 0);
-      sense.editor.focus();
-   }
-
-   function init() {
-
-      history_popup = $("#history_popup");
-
-
-      history_popup.on('shown', function () {
-         $('<div id="history_viewer">No history available</div>').appendTo(history_popup.find(".modal-body"));
-
-         history_viewer = ace.edit("history_viewer");
-         history_viewer.getSession().setMode("ace/mode/sense");
-//         history_viewer.setTheme("ace/theme/monokai");
-         history_viewer.getSession().setFoldStyle('markbeginend');
-         history_viewer.setReadOnly(true);
-         history_viewer.renderer.setShowPrintMargin(false);
-         sense.editor.getSession().setUseWrapMode(true);
-
-         $.each(getHistory(), function (i, hist_elem) {
-            var li = $('<li><a href="#"><i class="icon-chevron-right"></i><span/></a></li>');
-            var disc = hist_elem.endpoint;
-            var date = moment(hist_elem.time);
-            if (date.diff(moment(), "days") < -7)
-               disc += " (" + date.format("MMM D") + ")";
-            else
-               disc += " (" + date.fromNow() + ")";
-
-            li.find("span").text(disc);
-            li.attr("title", disc);
-
-            li.find("a").click(function () {
-               history_popup.find('.modal-body .nav li').removeClass("active");
-               li.addClass("active");
-               populateHistElem(hist_elem);
-               return false;
-            });
-
-            li.dblclick(function () {
-               li.addClass("active");
-               history_popup.find(".btn-primary").click();
-            });
-
-            li.hover(function () {
-               populateHistElem(hist_elem);
-               return false;
-            }, function () {
-               history_popup.find(".modal-body .nav li.active a").click();
-            });
-
-            li.bind('apply', function () {
-               applyHistElem(hist_elem);
+    const global = window;
+
+    let history_viewer, history_popup;
+
+    function getHistoryKeys() {
+        const keys = [];
+        for (let i = 0; i < localStorage.length; i++) {
+            const k = localStorage.key(i);
+            if (k.indexOf("hist_elem") === 0) {
+                keys.push(k);
+            }
+        }
+
+        keys.sort();
+        keys.reverse();
+        return keys;
+    }
+
+    function getHistory() {
+        const hist_items = [];
+        $.each(getHistoryKeys(), function (i, key) {
+            hist_items.push(JSON.parse(localStorage.getItem(key)));
+        });
+
+        return hist_items;
+    }
+
+    function getHistoricalServers() {
+        const servers = {};
+        $.each(getHistory(), function (i, h) {
+            servers[h.server] = 1;
+        });
+
+        const server_list = [];
+        for (const s in servers) server_list.push(s);
+
+        return server_list;
+    }
+
+    function populateHistElem(hist_elem) {
+        const s = hist_elem.method + " " + hist_elem.endpoint + "\n" + (hist_elem.data || "");
+        history_viewer.setValue(s);
+        history_viewer.clearSelection();
+    }
+
+    function applyHistElem(hist_elem) {
+        const session = sense.editor.getSession();
+        let pos = sense.editor.getCursorPosition();
+        let prefix = "";
+        let suffix = "\n";
+        if (sense.utils.isStartRequestRow(pos.row)) {
+            pos.column = 0;
+            suffix += "\n";
+        } else if (sense.utils.isEndRequestRow(pos.row)) {
+            const line = session.getLine(pos.row);
+            pos.column = line.length;
+            prefix = "\n\n";
+        } else if (sense.utils.isInBetweenRequestsRow(pos.row)) {
+            pos.column = 0;
+        } else {
+            pos = sense.utils.nextRequestEnd(pos);
+            prefix = "\n\n";
+        }
+
+        let s = prefix + hist_elem.method + " " + hist_elem.endpoint;
+        if (hist_elem.data) s += "\n" + hist_elem.data;
+
+        s += suffix;
+
+        session.insert(pos, s);
+        sense.editor.clearSelection();
+        sense.editor.moveCursorTo(pos.row + prefix.length, 0);
+        sense.editor.focus();
+    }
+
+    function init() {
+        history_popup = $("#history_popup");
+
+        history_popup.on('shown', function () {
+            $('<div id="history_viewer">No history available</div>').appendTo(history_popup.find(".modal-body"));
+
+            history_viewer = ace.edit("history_viewer");
+            history_viewer.getSession().setMode("ace/mode/sense");
+            history_viewer.getSession().setFoldStyle('markbeginend');
+            history_viewer.setReadOnly(true);
+            history_viewer.renderer.setShowPrintMargin(false);
+            sense.editor.getSession().setUseWrapMode(true);
+
+            $.each(getHistory(), function (i, hist_elem) {
+                const li = $('<li><a href="#"><i class="icon-chevron-right"></i><span/></a></li>');
+                let disc = hist_elem.endpoint;
+                const date = moment(hist_elem.time);
+                if (date.diff(moment(), "days") < -7)
+                    disc += " (" + date.format("MMM D") + ")";
+                else
+                    disc += " (" + date.fromNow() + ")";
+
+                li.find("span").text(disc);
+                li.attr("title", disc);
+
+                li.find("a").click(function () {
+                    history_popup.find('.modal-body .nav li').removeClass("active");
+                    li.addClass("active");
+                    populateHistElem(hist_elem);
+                    return false;
+                });
+
+                li.dblclick(function () {
+                    li.addClass("active");
+                    history_popup.find(".btn-primary").click();
+                });
+
+                li.hover(function () {
+                    populateHistElem(hist_elem);
+                    return false;
+                }, function () {
+                    history_popup.find(".modal-body .nav li.active a").click();
+                });
+
+                li.bind('apply', function () {
+                    applyHistElem(hist_elem);
+                });
+
+
+                li.appendTo(history_popup.find(".modal-body .nav"));
             });
 
+            history_popup.find(".modal-body .nav li:first a").click();
 
-            li.appendTo(history_popup.find(".modal-body .nav"));
-         });
+        });
 
-         history_popup.find(".modal-body .nav li:first a").click();
+        history_popup.on('hidden', function () {
+            history_popup.find('.modal-body #history_viewer').remove();
+            history_popup.find('.modal-body .nav li').remove();
+            history_viewer = null;
+        });
 
-      });
+        history_popup.find(".btn-primary").click(function () {
+            history_popup.find(".modal-body .nav li.active").trigger("apply");
+        });
 
-      history_popup.on('hidden', function () {
-         history_popup.find('.modal-body #history_viewer').remove();
-         history_popup.find('.modal-body .nav li').remove();
-         history_viewer = null;
-      });
+        history_popup.find("#hist_clear").click(function () {
+            const keys = getHistoryKeys();
+            $.each(keys, function (i, k) {
+                localStorage.removeItem(k);
+            });
+            history_popup.find(".modal-body .nav").html("");
+            history_viewer.getSession().setValue("No history available");
+        })
 
-      history_popup.find(".btn-primary").click(function () {
-         history_popup.find(".modal-body .nav li.active").trigger("apply");
-      });
+    }
 
-      history_popup.find("#hist_clear").click(function () {
-         var keys = getHistoryKeys();
-         $.each(keys, function (i, k) {
+    function addToHistory(server, endpoint, method, data) {
+        const keys = getHistoryKeys();
+        keys.splice(0, 500); // only maintain most recent X;
+        $.each(keys, function (i, k) {
             localStorage.removeItem(k);
-         });
-         history_popup.find(".modal-body .nav").html("");
-         history_viewer.getSession().setValue("No history available");
-      })
-
-   }
-
-   function addToHistory(server, endpoint, method, data) {
-      var keys = getHistoryKeys();
-      keys.splice(0, 500); // only maintain most recent X;
-      $.each(keys, function (i, k) {
-         localStorage.removeItem(k);
-      });
-
-      var timestamp = new Date().getTime();
-      var k = "hist_elem_" + timestamp;
-      localStorage.setItem(k, JSON.stringify(
-         { 'time': timestamp, 'server': server, 'endpoint': endpoint, 'method': method, 'data': data }));
-   }
-
-   function saveCurrentEditorState(server, content) {
-      var timestamp = new Date().getTime();
-      localStorage.setItem("editor_state", JSON.stringify(
-         { 'time': timestamp, 'server': server, 'content': content }));
-
-   }
-
-   function getSavedEditorState(server, content) {
-      return JSON.parse(localStorage.getItem("editor_state"));
-   }
-
-   global.sense.history = {
-      init: init,
-      addToHistory: addToHistory,
-      getHistoricalServers: getHistoricalServers,
-      saveCurrentEditorState: saveCurrentEditorState,
-      getSavedEditorState: getSavedEditorState
-   };
+        });
+
+        const timestamp = new Date().getTime();
+        const k = "hist_elem_" + timestamp;
+        localStorage.setItem(k, JSON.stringify(
+            {'time': timestamp, 'server': server, 'endpoint': endpoint, 'method': method, 'data': data}));
+    }
+
+    function saveCurrentEditorState(server, content) {
+        const timestamp = new Date().getTime();
+        localStorage.setItem("editor_state", JSON.stringify(
+            {'time': timestamp, 'server': server, 'content': content}));
+
+    }
+
+    function getSavedEditorState() {
+        return JSON.parse(localStorage.getItem("editor_state"));
+    }
+
+    global.sense.history = {
+        init: init,
+        addToHistory: addToHistory,
+        getHistoricalServers: getHistoricalServers,
+        saveCurrentEditorState: saveCurrentEditorState,
+        getSavedEditorState: getSavedEditorState
+    };
 
 })();