diff --git a/common/content/abbreviations.js b/common/content/abbreviations.js
index 4822e97a..e353a719 100644
--- a/common/content/abbreviations.js
+++ b/common/content/abbreviations.js
@@ -105,7 +105,7 @@ var AbbrevHive = Class("AbbrevHive", Contexts.Hive, {
     },
 
     /** @property {boolean} True if there are no abbreviations. */
-    get empty() { return !values(this._store).find(util.identity); },
+    get empty() { return !values(this._store).find(identity); },
 
     /**
      * Adds a new abbreviation.
@@ -251,7 +251,7 @@ var Abbreviations = Module("abbreviations", {
         let match = this._match.exec(text);
         if (match)
             return this.hives.map(h => h.get(mode, match[2] || match[4] || match[6]))
-                       .find(util.identity);
+                       .find(identity);
         return null;
     },
 
diff --git a/common/content/bookmarks.js b/common/content/bookmarks.js
index aa14e32f..efb292ec 100644
--- a/common/content/bookmarks.js
+++ b/common/content/bookmarks.js
@@ -438,7 +438,7 @@ var Bookmarks = Module("bookmarks", {
                                              for (b of bookmarkcache)
                                              if (b.tags))
                                             .flatten().uniq().array;
-                context.keys = { text: util.identity, description: util.identity };
+                context.keys = { text: identity, description: identity };
             },
             type: CommandOption.LIST
         };
@@ -705,7 +705,7 @@ var Bookmarks = Module("bookmarks", {
                                 }
                                 catch (e) {}
                             return null;
-                        }).filter(util.identity);
+                        }).filter(identity);
                     };
                 });
         };
@@ -742,7 +742,7 @@ var Bookmarks = Module("bookmarks", {
                 let ctxt = context.fork(name, 0);
 
                 ctxt.title = [/*L*/desc + " Suggestions"];
-                ctxt.keys = { text: util.identity, description: function () "" };
+                ctxt.keys = { text: identity, description: function () "" };
                 ctxt.compare = CompletionContext.Sort.unsorted;
                 ctxt.filterFunc = null;
 
diff --git a/common/content/commandline.js b/common/content/commandline.js
index 28ee5561..55717f26 100644
--- a/common/content/commandline.js
+++ b/common/content/commandline.js
@@ -166,7 +166,7 @@ var CommandWidgets = Class("CommandWidgets", {
         this.elements[obj.name] = obj;
 
         function get(prefix, map, id) {
-            return (obj.getElement || util.identity)(map[id] || document.getElementById(prefix + id));
+            return (obj.getElement || identity)(map[id] || document.getElementById(prefix + id));
         }
 
         this.active.__defineGetter__(obj.name, () => this.activeGroup[obj.name][obj.name]);
@@ -200,7 +200,7 @@ var CommandWidgets = Class("CommandWidgets", {
                         else {
                             highlight.highlightNode(elem,
                                 (val[0] != null ? val[0] : obj.defaultGroup)
-                                    .split(/\s/).filter(util.identity)
+                                    .split(/\s/).filter(identity)
                                     .map(g => g + " " + nodeSet.group + g)
                                     .join(" "));
                             elem.value = val[1];
diff --git a/common/content/dactyl.js b/common/content/dactyl.js
index e1bc814f..f7e430d6 100644
--- a/common/content/dactyl.js
+++ b/common/content/dactyl.js
@@ -256,7 +256,7 @@ var Dactyl = Module("dactyl", XPCOM(Ci.nsISupportsWeakReference, ModuleBase), {
             {
                 argCount: "*",
                 completer: function (context, args) {
-                    context.keys.text = util.identity;
+                    context.keys.text = identity;
                     context.keys.description = function () {
                         return seen[this.text] + /*L*/" matching items";
                     };
@@ -662,7 +662,7 @@ var Dactyl = Module("dactyl", XPCOM(Ci.nsISupportsWeakReference, ModuleBase), {
      */
     generateHelp: function generateHelp(obj, extraHelp, str, specOnly) {
         let link, tag, spec;
-        link = tag = spec = util.identity;
+        link = tag = spec = identity;
         let args = null;
 
         if (obj instanceof Command) {
@@ -1286,7 +1286,7 @@ var Dactyl = Module("dactyl", XPCOM(Ci.nsISupportsWeakReference, ModuleBase), {
                        template.map(iter(dactyl.indices),
                                     ([name, iter]) =>
                            ["dl", { insertafter: name + "-index" },
-                               template.map(iter(), util.identity)],
+                               template.map(iter(), identity)],
                            "\n\n")]);
         }, true);
 
diff --git a/common/content/editor.js b/common/content/editor.js
index 252abb93..8ff52b17 100644
--- a/common/content/editor.js
+++ b/common/content/editor.js
@@ -777,7 +777,7 @@ var Editor = Module("editor", XPCOM(Ci.nsIEditActionListener, ModuleBase), {
     completion: function initCompletion() {
         completion.register = function complete_register(context) {
             context = context.fork("registers");
-            context.keys = { text: util.identity, description: editor.bound.getRegister };
+            context.keys = { text: identity, description: editor.bound.getRegister };
 
             context.match = function (r) {
                 return !this.filter || this.filter.contains(r);
@@ -1413,7 +1413,7 @@ var Editor = Module("editor", XPCOM(Ci.nsIEditActionListener, ModuleBase), {
                     let res = {};
                     services.spell.getDictionaryList(res, {});
                     context.completions = res.value;
-                    context.keys = { text: util.identity, description: util.identity };
+                    context.keys = { text: identity, description: identity };
                 }
             });
     },
diff --git a/common/content/history.js b/common/content/history.js
index fe410d73..c3cdfdf5 100644
--- a/common/content/history.js
+++ b/common/content/history.js
@@ -331,7 +331,7 @@ var History = Module("history", {
         completion.domain = context => {
             context.anchored = false;
             context.compare = (a, b) => String.localeCompare(a.key, b.key);
-            context.keys = { text: util.identity, description: util.identity,
+            context.keys = { text: identity, description: identity,
                 key: function (host) host.split(".").reverse().join(".") };
 
             // FIXME: Schema-specific
diff --git a/common/content/mappings.js b/common/content/mappings.js
index 20f49f3d..873cd3e9 100644
--- a/common/content/mappings.js
+++ b/common/content/mappings.js
@@ -196,7 +196,7 @@ var MapHive = Class("MapHive", Contexts.Hive, {
      */
     add: function (modes, keys, description, action, extra={}) {
         modes = Array.concat(modes);
-        if (!modes.every(util.identity))
+        if (!modes.every(identity))
             throw TypeError(/*L*/"Invalid modes: " + modes);
 
         let map = Map(modes, keys, description, action, extra);
diff --git a/common/content/marks.js b/common/content/marks.js
index 326153f4..ba461638 100644
--- a/common/content/marks.js
+++ b/common/content/marks.js
@@ -301,14 +301,14 @@ var Marks = Module("marks", {
                     "(" + Math.round(mark.offset.x * 100),
                           Math.round(mark.offset.y * 100) + ")",
                     (tab && "tab: " + tabs.index(tab))
-            ].filter(util.identity).join(", ");
+            ].filter(identity).join(", ");
 
         if (mark.position)
             return [name, mark.location,
                     "(" + Math.round(mark.position.x * 100) + "%",
                           Math.round(mark.position.y * 100) + "%)",
                     (tab && "tab: " + tabs.index(tab))
-            ].filter(util.identity).join(", ");
+            ].filter(identity).join(", ");
     },
 
     isLocalMark: bind("test", /^[a-z`']$/),
diff --git a/common/modules/base.jsm b/common/modules/base.jsm
index 7b5acf50..34754a96 100644
--- a/common/modules/base.jsm
+++ b/common/modules/base.jsm
@@ -201,6 +201,7 @@ defineModule("base", {
         "deprecated",
         "endModule",
         "hasOwnProperty",
+        "identity",
         "isArray",
         "isGenerator",
         "isObject",
@@ -724,6 +725,14 @@ function call(fn, self, ...args) {
     return fn;
 }
 
+/**
+ * Returns *val*.
+ *
+ * @param {*} val
+ * @returns {*}
+ */
+function identity(val) { return val; }
+
 /**
  * Memoizes an object property value.
  *
@@ -1632,7 +1641,7 @@ update(iter, {
     compact: function compact(iter) (item for (item of iter) if (item != null)),
 
     every: function every(iter, pred, self) {
-        pred = pred || util.identity;
+        pred = pred || identity;
         for (let elem of iter)
             if (!pred.call(self, elem))
                 return false;
@@ -1640,7 +1649,7 @@ update(iter, {
     },
 
     some: function every(iter, pred, self) {
-        pred = pred || util.identity;
+        pred = pred || identity;
         for (let elem of iter)
             if (pred.call(self, elem))
                 return true;
diff --git a/common/modules/buffer.jsm b/common/modules/buffer.jsm
index 17bbb8a4..42a404fd 100644
--- a/common/modules/buffer.jsm
+++ b/common/modules/buffer.jsm
@@ -2552,7 +2552,7 @@ var Buffer = Module("Buffer", {
                                 res = iter.find(filter.matcher(doc),
                                                 elem => ((elem.nodeValue || elem.textContent).trim() == line &&
                                                          DOM(elem).display != "none"))
-                                   || iter.nth(filter.matcher(doc), util.identity, line - 1);
+                                   || iter.nth(filter.matcher(doc), identity, line - 1);
                             if (res)
                                 break;
                         }
diff --git a/common/modules/commands.jsm b/common/modules/commands.jsm
index a6945f31..ead17c3a 100644
--- a/common/modules/commands.jsm
+++ b/common/modules/commands.jsm
@@ -917,7 +917,7 @@ var Commands = Module("commands", {
      * @returns {Command}
      */
     get: function get(name, full) iter(this.hives).map(([i, hive]) => hive.get(name, full))
-                                                  .find(util.identity),
+                                                  .find(identity),
 
     /**
      * Returns true if a command invocation contains a URL referring to the
@@ -1569,7 +1569,7 @@ var Commands = Module("commands", {
             let quote = RegExp.$2;
             context.quote = null;
             context.offset -= idx;
-            context.filter = str.substr(0, idx) + (quote ? Option.quote : util.identity)(context.filter);
+            context.filter = str.substr(0, idx) + (quote ? Option.quote : identity)(context.filter);
 
             context.fork("ex", 0, completion, "ex");
         };
diff --git a/common/modules/completion.jsm b/common/modules/completion.jsm
index 722c4168..d05314ec 100644
--- a/common/modules/completion.jsm
+++ b/common/modules/completion.jsm
@@ -366,7 +366,7 @@ var CompletionContext = Class("CompletionContext", {
     get createRow() { return this._createRow || template.completionRow; }, // XXX
     set createRow(createRow) { return this._createRow = createRow; },
 
-    get filterFunc() { return this._filterFunc || util.identity; },
+    get filterFunc() { return this._filterFunc || identity; },
     set filterFunc(val) { this._filterFunc = val; },
 
     get filter() {
@@ -595,7 +595,7 @@ var CompletionContext = Class("CompletionContext", {
         if (this._substrings)
             return this._substrings;
 
-        let fixCase = this.ignoreCase ? String.toLowerCase : util.identity;
+        let fixCase = this.ignoreCase ? String.toLowerCase : identity;
         let text   = fixCase(items[0].text);
         let filter = fixCase(this.filter);
 
@@ -1035,7 +1035,7 @@ var Completion = Module("completion", {
         if (/^jar:[^!]*$/.test(context.filter)) {
             context.advance(4);
 
-            context.quote = context.quote || ["", util.identity, ""];
+            context.quote = context.quote || ["", identity, ""];
             let quote = context.quote[1];
             context.quote[1] = function quote_1(str) {
                 return quote(str.replace(/!/g, escape));
@@ -1185,7 +1185,7 @@ var Completion = Module("completion", {
                 });
             });
 
-            let re = RegExp(tokens.filter(util.identity).map(util.regexp.escape).join("|"), "g");
+            let re = RegExp(tokens.filter(identity).map(util.regexp.escape).join("|"), "g");
             function highlight(item, text, i) {
                 return process[i].call(this, item, template.highlightRegexp(text, re));
             }
diff --git a/common/modules/contexts.jsm b/common/modules/contexts.jsm
index 52aaec7f..0ba5c875 100644
--- a/common/modules/contexts.jsm
+++ b/common/modules/contexts.jsm
@@ -528,7 +528,7 @@ var Contexts = Module("contexts", {
             });
         }
 
-        let process = util.identity;
+        let process = identity;
 
         if (callable(params))
             var makeParams = function makeParams(self, args) {
@@ -663,7 +663,7 @@ var Contexts = Module("contexts", {
 
                 if (!group.builtin && args.has("-args")) {
                     group.argsExtra = contexts.bindMacro({ literalArg: "return " + args["-args"] },
-                                                         "-javascript", util.identity);
+                                                         "-javascript", identity);
                     group.args = args["-args"];
                 }
 
diff --git a/common/modules/dom.jsm b/common/modules/dom.jsm
index e11f1143..dbb5636f 100644
--- a/common/modules/dom.jsm
+++ b/common/modules/dom.jsm
@@ -659,7 +659,7 @@ var DOM = Class("DOM", {
                 res.push({}.toString.call(elem));
             }
         }, this);
-        res = template.map(res, util.identity, ",");
+        res = template.map(res, identity, ",");
         return color ? res : res.join("");
     },
 
diff --git a/common/modules/downloads.jsm b/common/modules/downloads.jsm
index 5bb4cbe4..cf91c287 100644
--- a/common/modules/downloads.jsm
+++ b/common/modules/downloads.jsm
@@ -165,7 +165,7 @@ var Download = Class("Download", {
         let val = this._compare[order.substr(1)](this, other);
 
         return (order[0] == "-") ? -val : val;
-    }, this).find(util.identity) || 0,
+    }, this).find(identity) || 0,
 
     timeRemaining: Infinity,
 
diff --git a/common/modules/io.jsm b/common/modules/io.jsm
index aecd6ab5..a93477fa 100644
--- a/common/modules/io.jsm
+++ b/common/modules/io.jsm
@@ -584,7 +584,7 @@ var IO = Module("io", {
         let args = Ary(util.range(0, func.length))
                     .map(bind("createTempFile", this, ext, label)).array;
         try {
-            if (!args.every(util.identity))
+            if (!args.every(identity))
                 return false;
             var res = func.apply(self || this, args);
         }
@@ -979,7 +979,7 @@ unlet s:cpo_save
         completion.charset = context => {
             context.anchored = false;
             context.keys = {
-                text: util.identity,
+                text: identity,
                 description: charset => io.charsetTitle(charset)
             };
             context.completions = io.charsets;
@@ -1163,7 +1163,7 @@ unlet s:cpo_save
             });
         options.add(["cdpath", "cd"],
             "List of directories searched when executing :cd",
-            "stringlist", ["."].concat(services.environment.get("CDPATH").split(/[:;]/).filter(util.identity)).join(","),
+            "stringlist", ["."].concat(services.environment.get("CDPATH").split(/[:;]/).filter(identity)).join(","),
             {
                 get files() {
                     return this.value.map(path => File(path, modules.io.cwd))
diff --git a/common/modules/options.jsm b/common/modules/options.jsm
index 9117412b..4122f0bc 100644
--- a/common/modules/options.jsm
+++ b/common/modules/options.jsm
@@ -1322,7 +1322,7 @@ var Options = Module("options", {
                             [option.stringValue, _("option.currentValue")],
                             [option.stringDefaultValue, _("option.defaultValue")]
                     ].filter(f => f[0] !== "");
-                    context.quote = ["", util.identity, ""];
+                    context.quote = ["", identity, ""];
                 });
             }
 
diff --git a/common/modules/sanitizer.jsm b/common/modules/sanitizer.jsm
index 3d48b06a..f6f496f1 100644
--- a/common/modules/sanitizer.jsm
+++ b/common/modules/sanitizer.jsm
@@ -620,7 +620,7 @@ var Sanitizer = Module("sanitizer", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakRef
             context.title = ["Domain"];
             context.anchored = false;
             context.compare = modules.CompletionContext.Sort.unsorted;
-            context.keys = { text: util.identity, description: util.identity };
+            context.keys = { text: identity, description: identity };
             context.completions = res;
         };
     },
diff --git a/common/modules/styles.jsm b/common/modules/styles.jsm
index 80693a94..eaf69f14 100644
--- a/common/modules/styles.jsm
+++ b/common/modules/styles.jsm
@@ -156,7 +156,7 @@ var Hive = Class("Hive", {
             sheet.sites = filter;
         }
         else {
-            sheet = Sheet(name, styles._id++, filter.filter(util.identity), String(css), this, agent);
+            sheet = Sheet(name, styles._id++, filter.filter(identity), String(css), this, agent);
             this.sheets.push(sheet);
         }
 
@@ -414,7 +414,7 @@ var Styles = Module("Styles", {
 
         context.generate = () => values(group.sites);
 
-        context.keys.text = util.identity;
+        context.keys.text = identity;
         context.keys.description = function (site) {
             return this.sheets.length + /*L*/" sheet" +
                    (this.sheets.length == 1 ? "" : "s") + ": " +
diff --git a/common/modules/util.jsm b/common/modules/util.jsm
index b0502e15..d60a6fa4 100644
--- a/common/modules/util.jsm
+++ b/common/modules/util.jsm
@@ -98,6 +98,8 @@ var Util = Module("Util", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference]),
     haveGecko: deprecated("config.haveGecko", { get: function haveGecko() config.bound.haveGecko }),
     OS: deprecated("config.OS", { get: function OS() config.OS }),
 
+    identity: deprecated("identity", { get: function identity() global.identity }),
+
     dactyl: update(function dactyl(obj) {
         if (obj)
             var global = Class.objectGlobal(obj);
@@ -346,7 +348,7 @@ var Util = Module("Util", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference]),
             return this[this.length - 1];
         });
 
-        let unknown = util.identity;
+        let unknown = identity;
         if (!keepUnknown)
             unknown = () => "";
 
@@ -395,7 +397,7 @@ var Util = Module("Util", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference]),
                 let [, flags, name] = /^((?:[a-z]-)*)(.*)/.exec(macro);
                 flags = new RealSet(flags);
 
-                let quote = util.identity;
+                let quote = identity;
                 if (flags.has("q"))
                     quote = function quote(obj) {
                         return typeof obj === "number" ? obj : JSON.stringify(obj);
@@ -851,14 +853,6 @@ var Util = Module("Util", XPCOM([Ci.nsIObserver, Ci.nsISupportsWeakReference]),
         });
     },
 
-    /**
-     * The identity function.
-     *
-     * @param {Object} k
-     * @returns {Object}
-     */
-    identity: function identity(k) k,
-
     /**
      * Returns the intersection of two rectangles.
      *