diff --git a/mod/bigbluebuttonbn/classes/completion/custom_completion.php b/mod/bigbluebuttonbn/classes/completion/custom_completion.php
index 3de9569e87d..7adb9b551c7 100644
--- a/mod/bigbluebuttonbn/classes/completion/custom_completion.php
+++ b/mod/bigbluebuttonbn/classes/completion/custom_completion.php
@@ -16,7 +16,9 @@
 
 namespace mod_bigbluebuttonbn\completion;
 
+use cm_info;
 use core_completion\activity_custom_completion;
+use mod_bigbluebuttonbn\extension;
 use mod_bigbluebuttonbn\instance;
 use mod_bigbluebuttonbn\logger;
 use moodle_exception;
@@ -44,6 +46,26 @@ class custom_completion extends activity_custom_completion {
         'completionengagementemojis' => [logger::EVENT_SUMMARY],
     ];
 
+    /**
+     * @var array $completionaddons array of extension class for the completion
+     */
+    private $completionaddons;
+
+    /**
+     * activity_custom_completion constructor.
+     *
+     * @param cm_info $cm
+     * @param int $userid
+     * @param array|null $completionstate The current state of the core completion criteria
+     */
+    public function __construct(cm_info $cm, int $userid, ?array $completionstate = null) {
+        parent::__construct($cm, $userid, $completionstate);
+        $completionaddonsclasses = extension::custom_completion_addons_instances($cm, $userid, $completionstate);
+        $this->completionaddons = array_map(function($targetclassname) use ($cm, $userid, $completionstate) {
+            return new $targetclassname($cm, $userid, $completionstate);
+        }, $completionaddonsclasses);
+    }
+
     /**
      * Get current state
      *
@@ -79,6 +101,12 @@ class custom_completion extends activity_custom_completion {
                 }
             }
         }
+        // Check for any completion for this rule in addons / extensions.
+        foreach ($this->completionaddons as $customcompletion) {
+            if (in_array($rule, $customcompletion->get_defined_custom_rules())) {
+                $returnedvalue = $returnedvalue || $customcompletion->get_state($rule);
+            }
+        }
         return $returnedvalue;
     }
 
@@ -109,7 +137,7 @@ class custom_completion extends activity_custom_completion {
      * @return array
      */
     public static function get_defined_custom_rules(): array {
-        return [
+        $rules = [
             'completionattendance',
             'completionengagementchats',
             'completionengagementtalks',
@@ -117,6 +145,11 @@ class custom_completion extends activity_custom_completion {
             'completionengagementpollvotes',
             'completionengagementemojis',
         ];
+        $completionaddonsclasses = extension::custom_completion_addons_classes();
+        foreach ($completionaddonsclasses as $customcompletion) {
+            $rules = array_merge($rules, $customcompletion::get_defined_custom_rules());
+        }
+        return $rules;
     }
 
     /**
@@ -131,7 +164,7 @@ class custom_completion extends activity_custom_completion {
         $completionengagementpollvotes = $this->cm->customdata['customcompletionrules']['completionengagementpollvotes'] ?? 1;
         $completionengagementemojis = $this->cm->customdata['customcompletionrules']['completionengagementemojis'] ?? 1;
         $completionattendance = $this->cm->customdata['customcompletionrules']['completionattendance'] ?? 1;
-        return [
+        $descriptions = [
             'completionengagementchats' => get_string('completionengagementchats_desc', 'mod_bigbluebuttonbn',
                 $completionengagementchats),
             'completionengagementtalks' => get_string('completionengagementtalks_desc', 'mod_bigbluebuttonbn',
@@ -145,6 +178,11 @@ class custom_completion extends activity_custom_completion {
             'completionattendance' => get_string('completionattendance_desc', 'mod_bigbluebuttonbn',
                 $completionattendance),
         ];
+        // Check for any completion for this rule in addons / extensions.
+        foreach ($this->completionaddons as $customcompletion) {
+            $descriptions = array_merge($descriptions, $customcompletion->get_custom_rule_descriptions());
+        }
+        return $descriptions;
     }
 
     /**
@@ -153,15 +191,9 @@ class custom_completion extends activity_custom_completion {
      * @return array
      */
     public function get_sort_order(): array {
-        return [
-            'completionview',
-            'completionengagementchats',
-            'completionengagementtalks',
-            'completionengagementraisehand',
-            'completionengagementpollvotes',
-            'completionengagementemojis',
-            'completionattendance',
-        ];
+        $rules = self::get_defined_custom_rules();
+        array_unshift($rules, 'completionview');
+        return $rules;
     }
 
     /**
diff --git a/mod/bigbluebuttonbn/classes/extension.php b/mod/bigbluebuttonbn/classes/extension.php
index 3162b43426e..b17bcc12e59 100644
--- a/mod/bigbluebuttonbn/classes/extension.php
+++ b/mod/bigbluebuttonbn/classes/extension.php
@@ -16,7 +16,9 @@
 namespace mod_bigbluebuttonbn;
 
 use cache;
+use cm_info;
 use mod_bigbluebuttonbn\local\extension\action_url_addons;
+use mod_bigbluebuttonbn\local\extension\custom_completion_addons;
 use mod_bigbluebuttonbn\local\extension\mod_form_addons;
 use mod_bigbluebuttonbn\local\extension\mod_instance_helper;
 use stdClass;
@@ -114,6 +116,27 @@ class extension {
         return $extensionclasses;
     }
 
+    /**
+     * Get all custom_completion addons classes.
+     *
+     * @return array of custom completion addon classes.
+     */
+    public static function custom_completion_addons_classes(): array {
+        return self::get_classes_implementing(custom_completion_addons::class);
+    }
+
+    /**
+     * Get all custom_completion addons classes instances.
+     *
+     * @param cm_info $cm
+     * @param int $userid
+     * @param array|null $completionstate
+     * @return array of custom completion addon instances.
+     */
+    public static function custom_completion_addons_instances(cm_info $cm, int $userid, ?array $completionstate = null): array {
+        return self::get_instances_implementing(custom_completion_addons::class, [$cm, $userid, $completionstate]);
+    }
+
     /**
      * Get all mod_form addons classes instances
      *
diff --git a/mod/bigbluebuttonbn/classes/local/extension/custom_completion_addons.php b/mod/bigbluebuttonbn/classes/local/extension/custom_completion_addons.php
new file mode 100644
index 00000000000..beec30a56df
--- /dev/null
+++ b/mod/bigbluebuttonbn/classes/local/extension/custom_completion_addons.php
@@ -0,0 +1,79 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+namespace mod_bigbluebuttonbn\local\extension;
+
+use cm_info;
+
+/**
+ * A class to deal with completion rules addons in a subplugin
+ *
+ * @package   mod_bigbluebuttonbn
+ * @copyright 2023 onwards, Blindside Networks Inc
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @author    Laurent David (laurent@call-learning.fr)
+ */
+abstract class custom_completion_addons {
+    /** @var cm_info The course module information object. */
+    protected $cm;
+
+    /** @var int The user's ID. */
+    protected $userid;
+
+    /** @var array The current state of core completion */
+    protected $completionstate;
+
+    /**
+     * activity_custom_completion constructor.
+     *
+     * @param cm_info $cm
+     * @param int $userid
+     * @param array|null $completionstate The current state of the core completion criteria
+     */
+    public function __construct(cm_info $cm, int $userid, ?array $completionstate = null) {
+        $this->cm = $cm;
+        $this->userid = $userid;
+        $this->completionstate = $completionstate;
+    }
+
+    /**
+     * Fetches the completion state for a given completion rule.
+     *
+     * @param string $rule The completion rule.
+     * @return int The completion state.
+     */
+    abstract public function get_state(string $rule): int;
+
+    /**
+     * Fetch the list of custom completion rules that this module defines.
+     *
+     * @return array
+     */
+    abstract public static function get_defined_custom_rules(): array;
+
+    /**
+     * Returns an associative array of the descriptions of custom completion rules.
+     *
+     * @return array
+     */
+    abstract public function get_custom_rule_descriptions(): array;
+
+    /**
+     * Returns an array of all completion rules, in the order they should be displayed to users.
+     *
+     * @return array
+     */
+    abstract public function get_sort_order(): array;
+}
diff --git a/mod/bigbluebuttonbn/classes/local/plugins/admin_plugin_manager.php b/mod/bigbluebuttonbn/classes/local/plugins/admin_plugin_manager.php
index ad752446e68..5c4be21dfb5 100644
--- a/mod/bigbluebuttonbn/classes/local/plugins/admin_plugin_manager.php
+++ b/mod/bigbluebuttonbn/classes/local/plugins/admin_plugin_manager.php
@@ -251,6 +251,8 @@ class admin_plugin_manager {
         $class = \core_plugin_manager::resolve_plugininfo_class(extension::BBB_EXTENSION_PLUGIN_NAME);
         $class::enable_plugin($plugin, false);
         cache_helper::purge_by_event('mod_bigbluebuttonbn/pluginenabledisabled');
+        // Also clear the cache for all BigBlueButtonModules.
+        rebuild_course_cache(0, true);
         return 'view';
     }
 
diff --git a/mod/bigbluebuttonbn/classes/local/proxy/recording_proxy.php b/mod/bigbluebuttonbn/classes/local/proxy/recording_proxy.php
index f3df3de5d11..777f277badd 100644
--- a/mod/bigbluebuttonbn/classes/local/proxy/recording_proxy.php
+++ b/mod/bigbluebuttonbn/classes/local/proxy/recording_proxy.php
@@ -49,7 +49,7 @@ class recording_proxy extends proxy_base {
      * @param string $recordid a recording id
      * @return bool
      */
-    public static function delete_recording(string $recordid, ?int $instanceid = null): bool {
+    public static function delete_recording(string $recordid): bool {
         $result = self::fetch_endpoint_xml('deleteRecordings', ['recordID' => $recordid]);
         if (!$result || $result->returncode != 'SUCCESS') {
             return false;
diff --git a/mod/bigbluebuttonbn/tests/behat/edit_instance.feature b/mod/bigbluebuttonbn/tests/behat/edit_instance.feature
index a47a2409e4a..d303818dc06 100644
--- a/mod/bigbluebuttonbn/tests/behat/edit_instance.feature
+++ b/mod/bigbluebuttonbn/tests/behat/edit_instance.feature
@@ -37,9 +37,9 @@ Feature: I can edit a bigbluebutton instance
       | bigbluebuttonbn_meetingevents_enabled        | 1 |
     And the following "users" exist:
       | username | firstname | lastname |
-      | student1 | Student1   | 1        |
+      | student1 | Student1  | 1        |
     And the following "course enrolments" exist:
-      | user     | course      | role           |
+      | user     | course      | role    |
       | student1 | Test course | student |
     And I am on the "RoomRecordings" "bigbluebuttonbn activity editing" page logged in as "admin"
     And I expand all fieldsets
diff --git a/mod/bigbluebuttonbn/tests/behat/subplugins.feature b/mod/bigbluebuttonbn/tests/behat/subplugins.feature
index 9a0dab11973..ede760905f5 100644
--- a/mod/bigbluebuttonbn/tests/behat/subplugins.feature
+++ b/mod/bigbluebuttonbn/tests/behat/subplugins.feature
@@ -3,14 +3,15 @@ Feature: BigBlueButtonBN Subplugins test
   As a BigBlueButtonBN user
   I can list the subplugins the admin settings pages
   I can see the additional settings coming from the subplugins in the edit form
+
   Background:  Make sure that the BigBlueButtonBN plugin is enabled
     Given I accept dpa and enable bigbluebuttonbn plugin
     And the following "courses" exist:
-      | fullname    | shortname   | category |
-      | Test course | Test course | 0        |
+      | fullname    | shortname   | category | enablecompletion |
+      | Test course | Test course | 0        | 1                |
     And the following "activities" exist:
-      | activity        | course          | name                | type |
-      | bigbluebuttonbn | Test course     | BBB Instance name   | 0    |
+      | activity        | course      | name              | type |
+      | bigbluebuttonbn | Test course | BBB Instance name | 0    |
 
   Scenario: Add a subplugin and check that the settings are available
     Given I log in as "admin"
@@ -43,3 +44,44 @@ Feature: BigBlueButtonBN Subplugins test
     And I am on the "BBB Instance name" "bigbluebuttonbn activity editing" page
     When I expand all fieldsets
     Then I should not see "New field"
+
+  @javascript
+  Scenario: I check that custom completion with subplugin works
+    Given a BigBlueButton mock server is configured
+    And the following config values are set as admin:
+      | bigbluebuttonbn_meetingevents_enabled | 1 |
+    And the following "users" exist:
+      | username | firstname | lastname | email                 |
+      | traverst | Terry     | Travers  | t.travers@example.com |
+    And the following "course enrolments" exist:
+      | user     | course      | role    |
+      | traverst | Test course | student |
+    And I am on the "BBB Instance name" "bigbluebuttonbn activity editing" page logged in as "admin"
+    And I expand all fieldsets
+    And I set the following fields to these values:
+      | Add requirements | 1 |
+      | Raise hand twice | 1 |
+    And I set the field "New field" to "50"
+    And I press "Save and display"
+    # We start the meeting here so to make sure that meta_analytics-callback-url is set.
+    And the following "mod_bigbluebuttonbn > meeting" exists:
+      | activity | BBB Instance name |
+    And I log out
+    And I am on the "BBB Instance name" "bigbluebuttonbn activity" page logged in as "traverst"
+    And I click on "Join session" "link"
+    And I switch to "bigbluebutton_conference" window
+    And I wait until the page is ready
+    And I follow "End Meeting"
+    And the BigBlueButtonBN server has received the following events from user "traverst":
+      | instancename      | eventtype | eventdata |
+      | BBB Instance name | raisehand | 1         |
+      | BBB Instance name | raisehand | 1         |
+    # Selenium driver does not like the click action to be done before we
+    # automatically close the window so we need to make sure that the window
+    # is closed before.
+    And I close all opened windows
+    And I switch to the main window
+    And the BigBlueButtonBN activity "BBB Instance name" has sent recording all its events
+    And I run all adhoc tasks
+    When I reload the page
+    Then I should see "Done: Raise hand twice in a meeting."
diff --git a/mod/bigbluebuttonbn/tests/completion/completion_test.php b/mod/bigbluebuttonbn/tests/completion/completion_test.php
index 4870447881e..99ce8697901 100644
--- a/mod/bigbluebuttonbn/tests/completion/completion_test.php
+++ b/mod/bigbluebuttonbn/tests/completion/completion_test.php
@@ -19,7 +19,6 @@ namespace mod_bigbluebuttonbn\completion;
 use completion_info;
 use context_module;
 use mod_bigbluebuttonbn\instance;
-use mod_bigbluebuttonbn\local\config;
 use mod_bigbluebuttonbn\logger;
 use mod_bigbluebuttonbn\meeting;
 use mod_bigbluebuttonbn\test\testcase_helper_trait;
diff --git a/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/custom_completion_addons.php b/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/custom_completion_addons.php
new file mode 100644
index 00000000000..a5edba0019c
--- /dev/null
+++ b/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/custom_completion_addons.php
@@ -0,0 +1,82 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+namespace bbbext_simple\bigbluebuttonbn;
+
+use mod_bigbluebuttonbn\instance;
+use mod_bigbluebuttonbn\logger;
+
+/**
+ * A class to deal with completion rules addons in a subplugin
+ *
+ * @package   mod_bigbluebuttonbn
+ * @copyright 2023 onwards, Blindside Networks Inc
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @author    Laurent David (laurent@call-learning.fr)
+ */
+class custom_completion_addons extends \mod_bigbluebuttonbn\local\extension\custom_completion_addons {
+
+    /**
+     * Get defined custom rule
+     *
+     * @return string[]
+     */
+    public static function get_defined_custom_rules(): array {
+        return ['completionextraisehandtwice'];
+    }
+
+    /**
+     * Get state
+     *
+     * @param string $rule
+     * @return int
+     */
+    public function get_state(string $rule): int {
+        $instance = instance::get_from_cmid($this->cm->id);
+        $logs = logger::get_user_completion_logs($instance, $this->userid, [logger::EVENT_SUMMARY]);
+        $raisehandcount = 0;
+        foreach ($logs as $log) {
+            $summary = json_decode($log->meta);
+            $raisehandcount += intval($summary->data->engagement->raisehand ?? 0);
+        }
+        if ($raisehandcount >= 2) {
+            return COMPLETION_COMPLETE;
+        }
+        return COMPLETION_INCOMPLETE;
+    }
+
+    /**
+     * Get rule description
+     *
+     * @return array
+     * @throws \coding_exception
+     */
+    public function get_custom_rule_descriptions(): array {
+        return [
+            'completionextraisehandtwice' => get_string('completionextraisehandtwice_desc', 'bbbext_simple'),
+        ];
+    }
+
+    /**
+     * Get sort order
+     *
+     * @return string[]
+     */
+    public function get_sort_order(): array {
+        return [
+            'completionattendance',
+        ];
+    }
+}
diff --git a/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/mod_form_addons.php b/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/mod_form_addons.php
index e9dd30d760b..bd7e0155dcc 100644
--- a/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/mod_form_addons.php
+++ b/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/mod_form_addons.php
@@ -69,7 +69,14 @@ class mod_form_addons extends \mod_bigbluebuttonbn\local\extension\mod_form_addo
      * @return array Array of string IDs of added items, empty array if none
      */
     public function add_completion_rules(): array {
-        return [];
+        $this->mform->addElement('advcheckbox', 'completionextraisehandtwice',
+            get_string('completionextraisehandtwice', 'bbbext_simple'),
+            get_string('completionextraisehandtwice_desc', 'bbbext_simple'));
+
+        $this->mform->addHelpButton('completionextraisehandtwice', 'completionextraisehandtwice',
+            'bbbext_simple');
+        $this->mform->disabledIf('completionextraisehandtwice', 'completion', 'neq', COMPLETION_AGGREGATION_ANY);
+        return ['completionextraisehandtwice' . $this->suffix];
     }
 
     /**
@@ -81,7 +88,7 @@ class mod_form_addons extends \mod_bigbluebuttonbn\local\extension\mod_form_addo
      *   default returns false
      */
     public function completion_rule_enabled(array $data): bool {
-        return false;
+        return !empty($data['completionextraisehandtwice' . $this->suffix]);
     }
 
     /**
@@ -111,7 +118,7 @@ class mod_form_addons extends \mod_bigbluebuttonbn\local\extension\mod_form_addo
      */
     public function validation(array $data, array $files): array {
         $errors = [];
-        if (empty($data['newfield'])) {
+        if (empty($data['newfield' . $this->suffix])) {
             $errors['newfield'] = get_string('newfielderror', 'bbbext_simple');
         }
         return $errors;
diff --git a/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/mod_instance_helper.php b/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/mod_instance_helper.php
index 813996a66be..86e0bcd32a3 100644
--- a/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/mod_instance_helper.php
+++ b/mod/bigbluebuttonbn/tests/fixtures/extension/simple/classes/bigbluebuttonbn/mod_instance_helper.php
@@ -35,7 +35,8 @@ class mod_instance_helper extends \mod_bigbluebuttonbn\local\extension\mod_insta
         global $DB;
         $DB->insert_record('bbbext_simple', (object) [
             'bigbluebuttonbnid' => $bigbluebuttonbn->id,
-            'newfield' => $bigbluebuttonbn->newfield ?? ''
+            'newfield' => $bigbluebuttonbn->newfield ?? '',
+            'completionextraisehandtwice' => $bigbluebuttonbn->completionextraisehandtwice ?? '',
         ]);
     }
 
@@ -54,9 +55,11 @@ class mod_instance_helper extends \mod_bigbluebuttonbn\local\extension\mod_insta
             $record = new stdClass();
             $record->bigbluebuttonbnid = $bigbluebuttonbn->id;
             $record->newfield = $bigbluebuttonbn->newfield ?? '';
+            $record->completionextraisehandtwice = $bigbluebuttonbn->completionextraisehandtwice ?? 0;
             $DB->insert_record('bbbext_simple', $record);
         } else {
             $record->newfield = $bigbluebuttonbn->newfield ?? '';
+            $record->completionextraisehandtwice = $bigbluebuttonbn->completionextraisehandtwice ?? 0;
             $DB->update_record('bbbext_simple', $record);
         }
     }
diff --git a/mod/bigbluebuttonbn/tests/fixtures/extension/simple/db/install.xml b/mod/bigbluebuttonbn/tests/fixtures/extension/simple/db/install.xml
index 27be9232c30..253d9b8281b 100644
--- a/mod/bigbluebuttonbn/tests/fixtures/extension/simple/db/install.xml
+++ b/mod/bigbluebuttonbn/tests/fixtures/extension/simple/db/install.xml
@@ -9,6 +9,7 @@
                 <FIELD NAME="id" TYPE="int" LENGTH="10" NOTNULL="true" SEQUENCE="true"/>
                 <FIELD NAME="bigbluebuttonbnid" TYPE="int" LENGTH="10" NOTNULL="false" SEQUENCE="false"/>
                 <FIELD NAME="newfield" TYPE="int" LENGTH="2" NOTNULL="false" SEQUENCE="false"/>
+                <FIELD NAME="completionextraisehandtwice" TYPE="int" LENGTH="9" NOTNULL="true" DEFAULT="0" SEQUENCE="false"/>
             </FIELDS>
             <KEYS>
                 <KEY NAME="primary" TYPE="primary" FIELDS="id"/>
diff --git a/mod/bigbluebuttonbn/tests/fixtures/extension/simple/lang/en/bbbext_simple.php b/mod/bigbluebuttonbn/tests/fixtures/extension/simple/lang/en/bbbext_simple.php
index 41f55b72143..fc3b2dbb21a 100644
--- a/mod/bigbluebuttonbn/tests/fixtures/extension/simple/lang/en/bbbext_simple.php
+++ b/mod/bigbluebuttonbn/tests/fixtures/extension/simple/lang/en/bbbext_simple.php
@@ -27,3 +27,6 @@ $string['config_extension'] = 'Sample config extension setting';
 $string['newfield'] = 'New field';
 $string['newfielderror'] = 'New field cannot be empty';
 $string['pluginname'] = 'Simple BigBlueButtonPlugin';
+$string['completionextraisehandtwice'] = 'Raise hand twice';
+$string['completionextraisehandtwice_desc'] = 'Raise hand twice in a meeting.';
+$string['completionextraisehandtwice_help'] = 'Raise hand twice in a meeting.';
diff --git a/mod/bigbluebuttonbn/tests/local/extension_test.php b/mod/bigbluebuttonbn/tests/local/extension_test.php
index be907af02a9..51d5460f111 100644
--- a/mod/bigbluebuttonbn/tests/local/extension_test.php
+++ b/mod/bigbluebuttonbn/tests/local/extension_test.php
@@ -17,6 +17,7 @@ namespace mod_bigbluebuttonbn\local;
 
 use backup;
 use backup_controller;
+use mod_bigbluebuttonbn\completion\custom_completion;
 use mod_bigbluebuttonbn\extension;
 use mod_bigbluebuttonbn\instance;
 use mod_bigbluebuttonbn\local\extension\mod_instance_helper;
@@ -258,6 +259,115 @@ class extension_test extends \advanced_testcase {
         $this->assertEquals(5, $oldfieldrecord->newfield);
     }
 
+    /**
+     * Test completion with and without addons.
+     *
+     * @param array $customcompletionrules
+     * @param array $events
+     * @param int $expectedstate
+     * @return void
+     * @dataProvider custom_completion_data_provider
+     * @covers \mod_bigbluebuttonbn\local\extension\custom_completion_addons
+     */
+    public function test_additional_completion(array $customcompletionrules, array $events, int $expectedstate): void {
+        // Enable plugin.
+        $this->enable_plugins(true);
+        $this->initialise_mock_server();
+        list($bbactivitycontext, $bbactivitycm, $bbactivity) = $this->create_instance(
+            $this->get_course(),
+            array_merge([
+                'completion' => '2',
+            ], $customcompletionrules)
+        );
+
+        $plugingenerator = $this->getDataGenerator()->get_plugin_generator('mod_bigbluebuttonbn');
+
+        $user = $this->getDataGenerator()->create_user();
+        $this->setUser($user);
+
+        // Now create a couple of events.
+        $instance = instance::get_from_instanceid($bbactivity->id);
+        set_config('bigbluebuttonbn_meetingevents_enabled', true);
+        $meeting = $plugingenerator->create_meeting([
+            'instanceid' => $instance->get_instance_id(),
+            'groupid' => $instance->get_group_id(),
+            'participants' => json_encode([$user->id]),
+        ]);
+        foreach ($events as $edesc) {
+            $plugingenerator->add_meeting_event($user, $instance, $edesc->name, $edesc->data ?? '');
+        }
+        $result = $plugingenerator->send_all_events($instance);
+        $this->assertNotEmpty($result->data);
+        $data = json_decode(json_encode($result->data));
+        meeting::meeting_events($instance, $data);
+        $completion = new custom_completion($bbactivitycm, $user->id);
+        $result = $completion->get_overall_completion_state();
+        $this->assertEquals($expectedstate, $result);
+
+    }
+
+    /**
+     * Data generator
+     *
+     * @return array[]
+     */
+    public static function custom_completion_data_provider(): array {
+        global $CFG;
+        require_once($CFG->libdir . '/completionlib.php');
+        return [
+            'simple' => [
+                'customcompletionrules' => [
+                    'completionengagementtalks' => 1,
+                    'completionextraisehandtwice' => 1,
+                ],
+                'events' => [
+                    (object) ['name' => 'talks'],
+                    (object) ['name' => 'raisehand'],
+                    (object) ['name' => 'raisehand'],
+                ],
+                'expectedstate' => COMPLETION_COMPLETE,
+            ],
+            'not right events' => [
+                'customcompletionrules' => [
+                    'completionextraisehandtwice' => 1,
+                ],
+                'events' => [
+                    (object) ['name' => 'chats'],
+                ],
+                'expectedstate' => COMPLETION_INCOMPLETE,
+            ],
+            'not enough events' => [
+                'customcompletionrules' => [
+                    'completionextraisehandtwice' => 1,
+                ],
+                'events' => [
+                    (object) ['name' => 'raisehand'],
+                ],
+                'expectedstate' => COMPLETION_INCOMPLETE,
+            ],
+            'more events' => [
+                'customcompletionrules' => [
+                    'completionengagementtalks' => 1,
+                ],
+                'events' => [
+                    (object) ['name' => 'talks'],
+                    (object) ['name' => 'talks'],
+                    (object) ['name' => 'talks'],
+                ],
+                'expectedstate' => COMPLETION_COMPLETE,
+            ],
+            'basics are still working' => [
+                'customcompletionrules' => [
+                    'completionengagementtalks' => 1,
+                ],
+                'events' => [
+                    (object) ['name' => 'talks'],
+                ],
+                'expectedstate' => COMPLETION_COMPLETE,
+            ],
+        ];
+    }
+
     /**
      * Data provider for testing get_class_implementing
      *
@@ -268,15 +378,15 @@ class extension_test extends \advanced_testcase {
             'mod_instance_helper with plugin disabled' => [
                 'bbbenabled' => false,
                 'apiclass' => mod_instance_helper::class,
-                'result' => []
+                'result' => [],
             ],
             'mod_instance_helper with plugin enabled' => [
                 'bbbenabled' => true,
                 'apiclass' => mod_instance_helper::class,
                 'result' => [
-                    'bbbext_simple\\bigbluebuttonbn\\mod_instance_helper'
-                ]
-            ]
+                    'bbbext_simple\\bigbluebuttonbn\\mod_instance_helper',
+                ],
+            ],
         ];
     }