diff --git a/common/content/editor.js b/common/content/editor.js
index accee372..0c8803ae 100644
--- a/common/content/editor.js
+++ b/common/content/editor.js
@@ -833,7 +833,7 @@ var Editor = Module("editor", XPCOM(Ci.nsIEditActionListener, ModuleBase), {
 
         // add mappings for commands like h,j,k,l,etc. in CARET, VISUAL and TEXT_EDIT mode
         function addMovementMap(keys, description, hasCount, caretModeMethod, caretModeArg, textEditCommand, visualTextEditCommand) {
-            let extraInfo = {
+            let extra = {
                 count: !!hasCount,
                 type: "operator"
             };
@@ -872,7 +872,7 @@ var Editor = Module("editor", XPCOM(Ci.nsIEditActionListener, ModuleBase), {
                         }
                     }
                 },
-                extraInfo);
+                extra);
 
             mappings.add([modes.CARET, modes.TEXT_EDIT, modes.OPERATOR], keys, description,
                 function ({ count }) {
@@ -885,7 +885,7 @@ var Editor = Module("editor", XPCOM(Ci.nsIEditActionListener, ModuleBase), {
                             caretExecute(false);
                     }
                 },
-                extraInfo);
+                extra);
         }
 
         // add mappings for commands like i,a,s,c,etc. in TEXT_EDIT mode
diff --git a/common/content/mappings.js b/common/content/mappings.js
index 5946fdab..787b9930 100644
--- a/common/content/mappings.js
+++ b/common/content/mappings.js
@@ -439,7 +439,7 @@ var Mappings = Module("mappings", {
      * @param {string} description A description of the key mapping.
      * @param {function} action The action invoked by each key sequence.
      * @param {Object} extra An optional extra configuration hash (see
-     *     {@link Map#extraInfo}).
+     *     {@link Map#extra}).
      * @optional
      */
     addUserMap: deprecated("group.mappings.add", function addUserMap() {
diff --git a/common/modules/commands.jsm b/common/modules/commands.jsm
index a2754fff..0ba1fb6e 100644
--- a/common/modules/commands.jsm
+++ b/common/modules/commands.jsm
@@ -113,8 +113,8 @@ update(CommandOption, {
  *     command name prefix.
  * @param {string} description A short one line description of the command.
  * @param {function} action The action invoked by this command when executed.
- * @param {Object} extraInfo An optional extra configuration hash. The
- *     following properties are supported.
+ * @param {Object} extra An optional extra configuration hash. The following
+ * properties are supported.
  *         always      - see {@link Command#always}
  *         argCount    - see {@link Command#argCount}
  *         bang        - see {@link Command#bang}
@@ -131,19 +131,19 @@ update(CommandOption, {
  * @private
  */
 var Command = Class("Command", {
-    init: function init(specs, description, action, extraInfo) {
+    init: function init(specs, description, action, extra) {
         specs = Array.concat(specs); // XXX
 
         this.specs = specs;
         this.description = description;
         this.action = action;
 
-        if (extraInfo.options)
-            this._options = extraInfo.options;
-        delete extraInfo.options;
+        if (extra.options)
+            this._options = extra.options;
+        delete extra.options;
 
-        if (extraInfo)
-            this.update(extraInfo);
+        if (extra)
+            this.update(extra);
     },
 
     get toStringParams() { return [this.name, this.hive.name]; },
diff --git a/common/modules/options.jsm b/common/modules/options.jsm
index 056d5a5a..70aa0d53 100644
--- a/common/modules/options.jsm
+++ b/common/modules/options.jsm
@@ -35,8 +35,8 @@ let ValueError = Class("ValueError", ErrorBase);
  * @param {string} description A short one line description of the option.
  * @param {string} type The option's value data type (see {@link Option#type}).
  * @param {string} defaultValue The default value for this option.
- * @param {Object} extraInfo An optional extra configuration hash. The
- *     following properties are supported.
+ * @param {Object} extra An optional extra configuration hash. The following
+ * properties are supported.
  *         completer   - see {@link Option#completer}
  *         domains     - see {@link Option#domains}
  *         getter      - see {@link Option#getter}
@@ -50,14 +50,14 @@ let ValueError = Class("ValueError", ErrorBase);
  * @private
  */
 var Option = Class("Option", {
-    init: function init(modules, names, description, defaultValue, extraInfo) {
+    init: function init(modules, names, description, defaultValue, extra) {
         this.modules = modules;
         this.name = names[0];
         this.realNames = names;
         this.description = description;
 
-        if (extraInfo)
-            this.update(extraInfo);
+        if (extra)
+            this.update(extra);
 
         this._defaultValue = defaultValue;
 
@@ -836,8 +836,8 @@ var OptionHive = Class("OptionHive", Contexts.Hive, {
         this.has = v => hasOwnProperty(this.values, v);
     },
 
-    add: function add(names, description, type, defaultValue, extraInfo) {
-        return this.modules.options.add(names, description, type, defaultValue, extraInfo);
+    add: function add(names, description, type, defaultValue, extra) {
+        return this.modules.options.add(names, description, type, defaultValue, extra);
     }
 });
 
@@ -952,20 +952,20 @@ var Options = Module("options", {
              * @param {string} type The option type (see {@link Option#type}).
              * @param {value} defaultValue The option's default value.
              * @param {Object} extra An optional extra configuration hash (see
-             *     {@link Map#extraInfo}).
+             *     {@link Map#extra}).
              * @optional
              */
-            add: function add(names, description, type, defaultValue, extraInfo) {
+            add: function add(names, description, type, defaultValue, extra) {
                 if (!util.isDactyl(Components.stack.caller))
                     deprecated.warn(add, "options.add", "group.options.add");
 
                 util.assert(type in Option.types, _("option.noSuchType", type),
                             false);
 
-                if (!extraInfo)
-                    extraInfo = {};
+                if (!extra)
+                    extra = {};
 
-                extraInfo.definedAt = contexts.getCaller(Components.stack.caller);
+                extra.definedAt = contexts.getCaller(Components.stack.caller);
 
                 let name = names[0];
                 if (name in this._optionMap) {
@@ -976,12 +976,12 @@ var Options = Module("options", {
                 let closure = () => this._optionMap[name];
 
                 memoize(this._optionMap, name,
-                        () => Option.types[type](modules, names, description, defaultValue, extraInfo));
+                        () => Option.types[type](modules, names, description, defaultValue, extra));
 
                 for (let alias of names.slice(1))
                     memoize(this._optionMap, alias, closure);
 
-                if (extraInfo.setter && (!extraInfo.scope || extraInfo.scope & Option.SCOPE_GLOBAL))
+                if (extra.setter && (!extra.scope || extra.scope & Option.SCOPE_GLOBAL))
                     if (this.dactyl.initialized)
                         closure().initValue();
                     else