--- a/browser/components/customizableui/content/customizeMode.inc.xul
+++ b/browser/components/customizableui/content/customizeMode.inc.xul
@@ -2,18 +2,27 @@
    - License, v. 2.0. If a copy of the MPL was not distributed with this
    - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
 
 <hbox id="customization-container" flex="1" hidden="true">
   <vbox flex="1" id="customization-palette-container">
     <label id="customization-header">
       &customizeMode.menuAndToolbars.header;
     </label>
+    <hbox id="customization-empty" hidden="true">
+      <label>&customizeMode.menuAndToolbars.empty;</label>
+      <label onclick="BrowserOpenAddonsMgr('addons://discovery/');"
+             onkeypress="BrowserOpenAddonsMgr('addons://discovery/');"
+             id="customization-more-tools"
+             class="text-link">
+        &customizeMode.menuAndToolbars.emptyLink;
+      </label>
+    </hbox>
     <vbox id="customization-palette" flex="1"/>
-    <spacer flex="1"/>
+    <spacer id="customization-spacer" flex="1"/>
     <hbox>
       <button id="customization-toolbar-visibility-button" label="&customizeMode.toolbars;" class="customizationmode-button" type="menu">
         <menupopup id="customization-toolbar-menu" onpopupshowing="onViewToolbarsPopupShowing(event)"/>
       </button>
       <spacer flex="1"/>
       <button id="customization-reset-button" oncommand="gCustomizeMode.reset();" label="&customizeMode.restoreDefaults;" class="customizationmode-button"/>
     </hbox>
   </vbox>

--- a/browser/components/customizableui/src/CustomizeMode.jsm
+++ b/browser/components/customizableui/src/CustomizeMode.jsm
@@ -43,16 +43,18 @@ function CustomizeMode(aWindow) {
   this.document = aWindow.document;
   this.browser = aWindow.gBrowser;
 
   // There are two palettes - there's the palette that can be overlayed with
   // toolbar items in browser.xul. This is invisible, and never seen by the
   // user. Then there's the visible palette, which gets populated and displayed
   // to the user when in customizing mode.
   this.visiblePalette = this.document.getElementById(kPaletteId);
+  this.paletteEmptyNotice = this.document.getElementById("customization-empty");
+  this.paletteSpacer = this.document.getElementById("customization-spacer");
 };
 
 CustomizeMode.prototype = {
   _changed: false,
   _transitioning: false,
   window: null,
   document: null,
   // areas is used to cache the customizable areas when in customization mode.
@@ -223,16 +225,18 @@ CustomizeMode.prototype = {
 
       CustomizableUI.addListener(this);
       window.PanelUI.endBatchUpdate();
       this._customizing = true;
       this._transitioning = false;
 
       // Show the palette now that the transition has finished.
       this.visiblePalette.hidden = false;
+      this.paletteSpacer.hidden = true;
+      this._updateEmptyPaletteNotice();
 
       this._handler.isEnteringCustomizeMode = false;
       this.dispatchToolboxEvent("customizationready");
       if (!this._wantToBeInCustomizeMode) {
         this.exit();
       }
     }.bind(this)).then(null, function(e) {
       ERROR(e);
@@ -268,17 +272,19 @@ CustomizeMode.prototype = {
 
     this._removePanelCustomizationPlaceholders();
 
     let window = this.window;
     let document = this.document;
     let documentElement = document.documentElement;
 
     // Hide the palette before starting the transition for increased perf.
+    this.paletteSpacer.hidden = false;
     this.visiblePalette.hidden = true;
+    this.paletteEmptyNotice.hidden = true;
 
     this._transitioning = true;
 
     Task.spawn(function() {
       yield this.depopulatePalette();
 
       yield this._doTransition(false);
 
@@ -908,19 +914,25 @@ CustomizeMode.prototype = {
         this.visiblePalette.appendChild(this.makePaletteItem(widget, "palette"));
       }
     }
   },
 
   _onUIChange: function() {
     this._changed = true;
     this._updateResetButton();
+    this._updateEmptyPaletteNotice();
     this.dispatchToolboxEvent("customizationchange");
   },
 
+  _updateEmptyPaletteNotice: function() {
+    let paletteItems = this.visiblePalette.getElementsByTagName("toolbarpaletteitem");
+    this.paletteEmptyNotice.hidden = !!paletteItems.length;
+  },
+
   _updateResetButton: function() {
     let btn = this.document.getElementById("customization-reset-button");
     btn.disabled = CustomizableUI.inDefaultState;
   },
 
   handleEvent: function(aEvent) {
     switch(aEvent.type) {
       case "toolbarvisibilitychange":

--- a/browser/components/customizableui/test/browser.ini
+++ b/browser/components/customizableui/test/browser.ini
@@ -32,16 +32,17 @@ skip-if = os == "mac"
 # Because of the specific widths, this test is fragile and has been disabled.
 # NB: it was designed for mac only, but started randomly failing there.
 skip-if = true
 
 [browser_914863_disabled_help_quit_buttons.js]
 [browser_918049_skipintoolbarset_dnd.js]
 [browser_923857_customize_mode_event_wrapping_during_reset.js]
 [browser_927717_customize_drag_empty_toolbar.js]
+[browser_932928_show_notice_when_palette_empty.js]
 
 [browser_934113_menubar_removable.js]
 # Because this test is about the menubar, it can't be run on mac
 skip-if = os == "mac"
 
 [browser_946320_tabs_from_other_computers.js]
 skip-if = os == "linux"
 

new file mode 100644
--- /dev/null
+++ b/browser/components/customizableui/test/browser_932928_show_notice_when_palette_empty.js
@@ -0,0 +1,35 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+// There should be an advert to get more addons when the palette is empty.
+add_task(function() {
+  yield startCustomizing();
+  let visiblePalette = document.getElementById("customization-palette");
+  let emptyPaletteNotice = document.getElementById("customization-empty");
+  is(emptyPaletteNotice.hidden, true, "The empty palette notice should not be shown when there are items in the palette.");
+
+  while (visiblePalette.childElementCount) {
+    gCustomizeMode.addToToolbar(visiblePalette.children[0]);
+  }
+  is(visiblePalette.childElementCount, 0, "There shouldn't be any items remaining in the visible palette.");
+  is(emptyPaletteNotice.hidden, false, "The empty palette notice should be shown when there are no items in the palette.");
+
+  yield endCustomizing();
+  yield startCustomizing();
+  visiblePalette = document.getElementById("customization-palette");
+  emptyPaletteNotice = document.getElementById("customization-empty");
+  is(emptyPaletteNotice.hidden, false,
+     "The empty palette notice should be shown when there are no items in the palette and cust. mode is re-entered.");
+
+  gCustomizeMode.removeFromArea(document.getElementById("wrapper-home-button"));
+  is(emptyPaletteNotice.hidden, true,
+     "The empty palette notice should not be shown when there is at least one item in the palette.");
+});
+
+add_task(function asyncCleanup() {
+  yield endCustomizing();
+  yield resetCustomization();
+});

--- a/browser/locales/en-US/chrome/browser/browser.dtd
+++ b/browser/locales/en-US/chrome/browser/browser.dtd
@@ -672,16 +672,18 @@ just addresses the organization to follo
 <!ENTITY social.learnMore.accesskey "l">
 <!ENTITY social.closeNotificationItem.label "Not Now">
 
 
 
 <!ENTITY customizeMode.tabTitle "Customize &brandShortName;">
 <!ENTITY customizeMode.menuAndToolbars.label "Menu and toolbars">
 <!ENTITY customizeMode.menuAndToolbars.header "More Tools to Add to the Menu and Toolbar">
+<!ENTITY customizeMode.menuAndToolbars.empty "Want more tools?">
+<!ENTITY customizeMode.menuAndToolbars.emptyLink "Choose from thousands of add-ons">
 <!ENTITY customizeMode.restoreDefaults "Restore Defaults">
 <!ENTITY customizeMode.toolbars "Show / Hide Toolbars">
 
 <!ENTITY social.chatBar.commandkey "c">
 <!ENTITY social.chatBar.label "Focus chats">
 <!ENTITY social.chatBar.accesskey "c">
 
 <!ENTITY social.markpageMenu.accesskey "P">