diff --git a/js/misc/systemActions.js b/js/misc/systemActions.js
index 3f0b2ec98..7607efc65 100644
--- a/js/misc/systemActions.js
+++ b/js/misc/systemActions.js
@@ -269,7 +269,7 @@ const SystemActions = GObject.registerClass({
 
     getMatchingActions(terms) {
         // terms is a list of strings
-        terms = terms.map((term) => term.toLowerCase());
+        terms = terms.map(term => term.toLowerCase());
 
         let results = [];
 
diff --git a/js/ui/altTab.js b/js/ui/altTab.js
index 46f4ed912..4cf18e672 100644
--- a/js/ui/altTab.js
+++ b/js/ui/altTab.js
@@ -1043,7 +1043,7 @@ class WindowList extends SwitcherPopup.SwitcherList {
             this.addItem(icon, icon.label);
             this.icons.push(icon);
 
-            icon._unmanagedSignalId = icon.window.connect('unmanaged', (window) => {
+            icon._unmanagedSignalId = icon.window.connect('unmanaged', window => {
                 this._removeWindow(window);
             });
         }
diff --git a/js/ui/calendar.js b/js/ui/calendar.js
index 797558ffa..88e008e2c 100644
--- a/js/ui/calendar.js
+++ b/js/ui/calendar.js
@@ -1073,7 +1073,7 @@ var CalendarMessageList = class CalendarMessageList {
         this._clearButton.set_x_align(Clutter.ActorAlign.END);
         this._clearButton.connect('clicked', () => {
             let sections = [...this._sections.keys()];
-            sections.forEach((s) => s.clear());
+            sections.forEach(s => s.clear());
         });
         box.add_actor(this._clearButton);
 
diff --git a/js/ui/popupMenu.js b/js/ui/popupMenu.js
index de642e5a4..b66f3c5d1 100644
--- a/js/ui/popupMenu.js
+++ b/js/ui/popupMenu.js
@@ -549,7 +549,7 @@ var PopupMenuBase = class {
     }
 
     _connectItemSignals(menuItem) {
-        menuItem._activeChangeId = menuItem.connect('notify::active', (menuItem) => {
+        menuItem._activeChangeId = menuItem.connect('notify::active', menuItem => {
             let active = menuItem.active;
             if (active && this._activeMenuItem != menuItem) {
                 if (this._activeMenuItem)
diff --git a/js/ui/runDialog.js b/js/ui/runDialog.js
index ea8104765..32545590c 100644
--- a/js/ui/runDialog.js
+++ b/js/ui/runDialog.js
@@ -104,7 +104,7 @@ class RunDialog extends ModalDialog.ModalDialog {
 
         this._history = new History.HistoryManager({ gsettingsKey: HISTORY_KEY,
                                                      entry: this._entryText });
-        this._entryText.connect('activate', (o) => {
+        this._entryText.connect('activate', o => {
             this.popModal();
             this._run(o.get_text(),
                       Clutter.get_current_event().get_state() & Clutter.ModifierType.CONTROL_MASK);
diff --git a/js/ui/windowManager.js b/js/ui/windowManager.js
index 3df1cd508..8d5db083b 100644
--- a/js/ui/windowManager.js
+++ b/js/ui/windowManager.js
@@ -713,7 +713,7 @@ var WindowManager = class {
         this._isWorkspacePrepended = false;
 
         this._switchData = null;
-        this._shellwm.connect('kill-switch-workspace', (shellwm) => {
+        this._shellwm.connect('kill-switch-workspace', shellwm => {
             if (this._switchData) {
                 if (this._switchData.inProgress)
                     this._switchWorkspaceDone(shellwm);
diff --git a/js/ui/windowMenu.js b/js/ui/windowMenu.js
index f2fb750bc..bb6a8df7b 100644
--- a/js/ui/windowMenu.js
+++ b/js/ui/windowMenu.js
@@ -178,7 +178,7 @@ var WindowMenu = class extends PopupMenu.PopupMenu {
         }
 
         let waitId = 0;
-        let id = global.display.connect('grab-op-end', (display) => {
+        let id = global.display.connect('grab-op-end', display => {
             display.disconnect(id);
             GLib.source_remove(waitId);