diff --git a/course/format/singleactivity/tests/behat/activity_navigation.feature b/course/format/singleactivity/tests/behat/activity_navigation.feature
new file mode 100644
index 00000000000..7d3aed1dcff
--- /dev/null
+++ b/course/format/singleactivity/tests/behat/activity_navigation.feature
@@ -0,0 +1,67 @@
+@format @format_singleactivity
+Feature: Activity navigation in a single activity course
+  In order to quickly switch to another activity in a single activity course with multiple (hidden) activities
+  As a teacher
+  I need to use the activity navigation controls in activities
+
+  Background:
+    Given the following "users" exist:
+      | username  | firstname  | lastname  | email                 |
+      | teacher1  | Teacher    | 1         | teacher1@example.com  |
+      | student1  | Student    | 1         | student1@example.com  |
+    And the following "courses" exist:
+      | fullname | shortname | format         | activitytype |
+      | Course 1 | C1        | singleactivity | forum        |
+    And the following "course enrolments" exist:
+      | user      | course  | role            |
+      | student1  | C1      | student         |
+      | teacher1  | C1      | editingteacher  |
+    And the following "activities" exist:
+      | activity   | name         | intro                       | course | idnumber  | section |
+      | assign     | Assignment 1 | Test assignment description | C1     | assign1   | 0       |
+      | chat       | Chat 1       | Test chat description       | C1     | chat1     | 0       |
+      | forum      | Forum 1      | Test forum description      | C1     | forum1    | 0       |
+
+  Scenario: Step through hidden activities in the course as a teacher.
+    Given I log in as "teacher1"
+    When I am on "Course 1" course homepage
+    # The first activity (Forum 1) won't have the previous activity link.
+    Then "#prev-activity-link" "css_element" should not exist
+    And I should see "Assignment 1 (hidden)" in the "#next-activity-link" "css_element"
+    And I follow "Assignment 1 (hidden)"
+    And I should see "Forum 1" in the "#prev-activity-link" "css_element"
+    And I should see "Chat 1 (hidden)" in the "#next-activity-link" "css_element"
+    And I follow "Chat 1 (hidden)"
+    And I should see "Assignment 1 (hidden)" in the "#prev-activity-link" "css_element"
+    And "#next-activity-link" "css_element" should not exist
+
+  Scenario: Jump to a hidden activity as a teacher
+    Given I log in as "teacher1"
+    When I am on "Course 1" course homepage
+    Then "Jump to..." "field" should exist
+    # The current activity (Forum 1) will not be listed.
+    And the "Jump to..." select box should not contain "Forum 1"
+    # Check drop down menu contents.
+    And the "Jump to..." select box should contain "Assignment 1 (hidden)"
+    And the "Jump to..." select box should contain "Chat 1 (hidden)"
+    # Jump to a hidden activity somewhere in the middle.
+    When I select "Assignment 1 (hidden)" from the "Jump to..." singleselect
+    Then I should see "Assignment 1"
+    And I should see "Forum 1" in the "#prev-activity-link" "css_element"
+    And I should see "Chat 1 (hidden)" in the "#next-activity-link" "css_element"
+    # Jump to the first activity.
+    And I select "Forum 1" from the "Jump to..." singleselect
+    And I should see "Assignment 1 (hidden)" in the "#next-activity-link" "css_element"
+    But "#prev-activity-link" "css_element" should not exist
+    # Jump to the last activity.
+    And I select "Chat 1 (hidden)" from the "Jump to..." singleselect
+    And I should see "Assignment 1 (hidden)" in the "#prev-activity-link" "css_element"
+    But "#next-activity-link" "css_element" should not exist
+
+  Scenario: The activity navigation controls are not available as a student.
+    Given I log in as "student1"
+    And I am on "Course 1" course homepage
+    # The first activity won't have the previous activity link.
+    Then "#prev-activity-link" "css_element" should not exist
+    And "#next-activity-link" "css_element" should not exist
+    And "Jump to..." "field" should not exist
diff --git a/lib/outputlib.php b/lib/outputlib.php
index 0462b35173e..aecd3f47db6 100644
--- a/lib/outputlib.php
+++ b/lib/outputlib.php
@@ -677,6 +677,12 @@ class theme_config {
      */
     public $precompiledcsscallback = null;
 
+    /**
+     * Whether the theme uses course index.
+     * @var bool
+     */
+    public $usescourseindex = false;
+
     /**
      * Load the config.php file for a particular theme, and return an instance
      * of this class. (That is, this is a factory method.)
@@ -754,7 +760,7 @@ class theme_config {
             'rendererfactory', 'csspostprocess', 'editor_sheets', 'editor_scss', 'rarrow', 'larrow', 'uarrow', 'darrow',
             'hidefromselector', 'doctype', 'yuicssmodules', 'blockrtlmanipulations', 'blockrendermethod',
             'scss', 'extrascsscallback', 'prescsscallback', 'csstreepostprocessor', 'addblockposition',
-            'iconsystem', 'precompiledcsscallback', 'haseditswitch');
+            'iconsystem', 'precompiledcsscallback', 'haseditswitch', 'usescourseindex');
 
         foreach ($config as $key=>$value) {
             if (in_array($key, $configurable)) {
diff --git a/lib/outputrenderers.php b/lib/outputrenderers.php
index 8c23b0136f7..692eb4f6279 100644
--- a/lib/outputrenderers.php
+++ b/lib/outputrenderers.php
@@ -955,8 +955,17 @@ class core_renderer extends renderer_base {
             return '';
         }
 
-        // Get a list of all the activities in the course.
         $course = $this->page->cm->get_course();
+        $courseformat = course_get_format($course);
+
+        // If the theme implements course index and the current course format uses course index and the current
+        // page layout is not 'frametop' (this layout does not support course index), show no links.
+        if ($this->page->theme->usescourseindex && $courseformat->uses_course_index() &&
+                $this->page->pagelayout !== 'frametop') {
+            return '';
+        }
+
+        // Get a list of all the activities in the course.
         $modules = get_fast_modinfo($course->id)->get_cms();
 
         // Put the modules into an array in order by the position they are shown in the course.
diff --git a/theme/boost/config.php b/theme/boost/config.php
index 6db5d20c210..141a07d140d 100644
--- a/theme/boost/config.php
+++ b/theme/boost/config.php
@@ -158,3 +158,4 @@ $THEME->requiredblocks = '';
 $THEME->addblockposition = BLOCK_ADDBLOCK_POSITION_FLATNAV;
 $THEME->iconsystem = \core\output\icon_system::FONTAWESOME;
 $THEME->haseditswitch = true;
+$THEME->usescourseindex = true;
diff --git a/theme/boost/tests/behat/blacklist.json b/theme/boost/tests/behat/blacklist.json
index e37f62b6c38..bbd3a20f5c7 100644
--- a/theme/boost/tests/behat/blacklist.json
+++ b/theme/boost/tests/behat/blacklist.json
@@ -2,6 +2,8 @@
     "features": [
         "lib/tests/behat/action_menu.feature",
         "blocks/tests/behat/hide_blocks.feature",
-        "blocks/tests/behat/move_blocks.feature"
+        "blocks/tests/behat/move_blocks.feature",
+        "course/tests/behat/activity_navigation.feature",
+        "course/tests/behat/activity_navigation_with_restrictions.feature"
     ]
 }
diff --git a/theme/boost/version.php b/theme/boost/version.php
index 5864b20f47b..60cffec1fd7 100644
--- a/theme/boost/version.php
+++ b/theme/boost/version.php
@@ -24,6 +24,6 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$plugin->version   = 2021052505;
+$plugin->version   = 2021052506;
 $plugin->requires  = 2021052500;
 $plugin->component = 'theme_boost';
diff --git a/theme/upgrade.txt b/theme/upgrade.txt
index b52dbc47e34..605cc11a824 100644
--- a/theme/upgrade.txt
+++ b/theme/upgrade.txt
@@ -1,6 +1,9 @@
 This files describes API changes in /theme/* themes,
 information provided here is intended especially for theme designer.
 
+=== 4.0 ===
+* A new theme config 'usescourseindex' allows a theme to specify whether it implements and uses course index.
+
 === 3.11 ===
 * The classname 'viewmode-cobmined' in course/management.php has been changed to 'viewmode-combined'