diff --git a/.upgradenotes/MDL-86699-2025112111183228.yml b/.upgradenotes/MDL-86699-2025112111183228.yml
new file mode 100644
index 00000000000..09afbc6a751
--- /dev/null
+++ b/.upgradenotes/MDL-86699-2025112111183228.yml
@@ -0,0 +1,7 @@
+issueNumber: MDL-86699
+notes:
+  mod_forum:
+    - message: >-
+        The forum report entity `->get_context_joins()` method is deprecated,
+        replaced with `->get_course_modules_joins(...)`
+      type: deprecated
diff --git a/public/mod/forum/classes/reportbuilder/datasource/forums.php b/public/mod/forum/classes/reportbuilder/datasource/forums.php
index 01b815c221e..96d074ecfc9 100644
--- a/public/mod/forum/classes/reportbuilder/datasource/forums.php
+++ b/public/mod/forum/classes/reportbuilder/datasource/forums.php
@@ -18,6 +18,7 @@ declare(strict_types=1);
 
 namespace mod_forum\reportbuilder\datasource;
 
+use core_course\reportbuilder\local\entities\{course_category, course_module};
 use core_reportbuilder\datasource;
 use core_reportbuilder\local\entities\{course, user};
 use mod_forum\reportbuilder\local\entities\{forum, discussion, post};
@@ -47,12 +48,13 @@ class forums extends datasource {
 
         [
             'context' => $contextalias,
+            'course_modules' => $coursemodulesalias,
             'forum' => $forumalias,
         ] = $forumentity->get_table_aliases();
 
         $this->set_main_table('forum', $forumalias);
         $this->add_entity($forumentity
-            ->add_joins($forumentity->get_context_joins()));
+            ->add_joins($forumentity->get_course_modules_joins('forum', "{$forumalias}.id")));
 
         // Join the course entity.
         $courseentity = new course();
@@ -60,6 +62,19 @@ class forums extends datasource {
         $this->add_entity($courseentity
             ->add_join("LEFT JOIN {course} {$coursealias} ON {$coursealias}.id = {$forumalias}.course"));
 
+        // Join the course category entity.
+        $coursecatentity = new course_category();
+        $coursecatalias = $coursecatentity->get_table_alias('course_categories');
+        $this->add_entity($coursecatentity
+            ->add_joins($courseentity->get_joins())
+            ->add_join("LEFT JOIN {course_categories} {$coursecatalias} ON {$coursecatalias}.id = {$coursealias}.category"));
+
+        // Join the course module entity.
+        $coursemodentity = (new course_module())
+            ->set_table_alias('course_modules', $coursemodulesalias);
+        $this->add_entity($coursemodentity
+            ->add_joins($forumentity->get_joins()));
+
         // Join the discussion entity.
         $discussionentity = (new discussion())
             ->set_table_alias('context', $contextalias);
@@ -84,7 +99,9 @@ class forums extends datasource {
             ->add_join("LEFT JOIN {user} {$useralias} ON {$useralias}.id = {$postalias}.userid"));
 
         // Add report elements from each of the entities we added to the report.
+        $this->add_all_from_entity($coursecatentity->get_entity_name());
         $this->add_all_from_entity($courseentity->get_entity_name());
+        $this->add_all_from_entity($coursemodentity->get_entity_name());
         $this->add_all_from_entity($forumentity->get_entity_name());
         $this->add_all_from_entity($discussionentity->get_entity_name());
         $this->add_all_from_entity($postentity->get_entity_name());
diff --git a/public/mod/forum/classes/reportbuilder/local/entities/forum.php b/public/mod/forum/classes/reportbuilder/local/entities/forum.php
index fe091a0d5f9..f8d8939748c 100644
--- a/public/mod/forum/classes/reportbuilder/local/entities/forum.php
+++ b/public/mod/forum/classes/reportbuilder/local/entities/forum.php
@@ -20,9 +20,9 @@ namespace mod_forum\reportbuilder\local\entities;
 
 use core\{context, context_helper};
 use core\lang_string;
-use core_reportbuilder\local\entities\base;
+use core_course\reportbuilder\local\entities\course_module_base;
 use core_reportbuilder\local\filters\{date, select, text};
-use core_reportbuilder\local\helpers\{database, format};
+use core_reportbuilder\local\helpers\format;
 use core_reportbuilder\local\report\{column, filter};
 use stdClass;
 
@@ -33,17 +33,19 @@ use stdClass;
  * @copyright   2025 Paul Holden <paulh@moodle.com>
  * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-class forum extends base {
+class forum extends course_module_base {
     /**
      * Database tables that this entity uses
      *
      * @return string[]
      */
     protected function get_default_tables(): array {
-        return [
-            'context',
-            'forum',
-        ];
+        return array_merge(
+            parent::get_default_tables(),
+            [
+                'forum',
+            ],
+        );
     }
 
     /**
@@ -228,20 +230,17 @@ class forum extends base {
      * Return context joins
      *
      * @return string[]
+     *
+     * @deprecated since Moodle 5.2 - please do not use this function any more, {@see get_course_modules_joins}
      */
+    #[\core\attribute\deprecated('::get_course_modules_joins', since: '5.2', mdl: 'MDL-86699')]
     public function get_context_joins(): array {
+        \core\deprecation::emit_deprecation([self::class, __FUNCTION__]);
+
         [
-            'context' => $contextalias,
             'forum' => $forumalias,
         ] = $this->get_table_aliases();
 
-        [$coursemodulealias, $modulealias] = database::generate_aliases(2);
-
-        return [
-            "JOIN {course_modules} {$coursemodulealias} ON {$coursemodulealias}.instance = {$forumalias}.id",
-            "JOIN {modules} {$modulealias} ON {$modulealias}.id = {$coursemodulealias}.module AND {$modulealias}.name = 'forum'",
-            "JOIN {context} {$contextalias} ON {$contextalias}.contextlevel = " . CONTEXT_MODULE . "
-                    AND {$contextalias}.instanceid = {$coursemodulealias}.id",
-        ];
+        return $this->get_course_modules_joins('forum', "{$forumalias}.id");
     }
 }
diff --git a/public/mod/forum/tests/reportbuilder/datasource/forums_test.php b/public/mod/forum/tests/reportbuilder/datasource/forums_test.php
index 674d7a1c93b..6e4248e93c5 100644
--- a/public/mod/forum/tests/reportbuilder/datasource/forums_test.php
+++ b/public/mod/forum/tests/reportbuilder/datasource/forums_test.php
@@ -109,7 +109,8 @@ final class forums_test extends core_reportbuilder_testcase {
         $this->resetAfterTest();
         $this->setAdminUser();
 
-        $course = $this->getDataGenerator()->create_course();
+        $category = $this->getDataGenerator()->create_category();
+        $course = $this->getDataGenerator()->create_course(['category' => $category->id]);
         $user = $this->getDataGenerator()->create_and_enrol($course);
 
         /** @var mod_forum_generator $generator */
@@ -117,6 +118,7 @@ final class forums_test extends core_reportbuilder_testcase {
 
         $forum = $generator->create_instance([
             'course' => $course->id,
+            'idnumber' => 'FORUM1',
             'intro' => 'My cool forum',
             'duedate' => $this->clock->time() + DAYSECS,
             'cutoffdate' => $this->clock->time() + WEEKSECS,
@@ -135,6 +137,12 @@ final class forums_test extends core_reportbuilder_testcase {
         $generator = $this->getDataGenerator()->get_plugin_generator('core_reportbuilder');
         $report = $generator->create_report(['name' => 'Forums', 'source' => forums::class, 'default' => 0]);
 
+        // Course category.
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'course_category:name']);
+
+        // Course module.
+        $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'course_module:idnumber']);
+
         // Forum.
         $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'forum:description']);
         $generator->create_column(['reportid' => $report->get('id'), 'uniqueidentifier' => 'forum:type']);
@@ -157,6 +165,8 @@ final class forums_test extends core_reportbuilder_testcase {
 
         $this->assertEquals([
             [
+                $category->get_formatted_name(),
+                'FORUM1',
                 '<div class="text_to_html">My cool forum</div>',
                 'Standard forum for general use',
                 'Wednesday, 2 June 2021, 7:00 AM',
@@ -180,6 +190,16 @@ final class forums_test extends core_reportbuilder_testcase {
      */
     public static function datasource_filters_provider(): array {
         return [
+            // Course category.
+            'Course category name' => ['course_category:text', [
+                'course_category:text_operator' => text::IS_EQUAL_TO,
+                'course_category:text_value' => 'My category',
+            ], true],
+            'Course category name (no match)' => ['course_category:text', [
+                'course_category:text_operator' => text::IS_EQUAL_TO,
+                'course_category:text_value' => 'Another category',
+            ], false],
+
             // Course.
             'Course fullname' => ['course:fullname', [
                 'course:fullname_operator' => text::IS_EQUAL_TO,
@@ -190,6 +210,16 @@ final class forums_test extends core_reportbuilder_testcase {
                 'course:fullname_value' => 'Another course',
             ], false],
 
+            // Course module.
+            'Course module ID number' => ['course_module:idnumber', [
+                'course_module:idnumber_operator' => text::IS_EQUAL_TO,
+                'course_module:idnumber_value' => 'FORUM1',
+            ], true],
+            'Course module ID number (no match)' => ['course_module:idnumber', [
+                'course_module:idnumber_operator' => text::IS_EQUAL_TO,
+                'course_module:idnumber_value' => 'FORUM2',
+            ], false],
+
             // Forum.
             'Forum name' => ['forum:name', [
                 'forum:name_operator' => text::IS_EQUAL_TO,
@@ -341,7 +371,8 @@ final class forums_test extends core_reportbuilder_testcase {
         $this->resetAfterTest();
         $this->setAdminUser();
 
-        $course = $this->getDataGenerator()->create_course(['fullname' => 'My course']);
+        $category = $this->getDataGenerator()->create_category(['name' => 'My category']);
+        $course = $this->getDataGenerator()->create_course(['category' => $category->id, 'fullname' => 'My course']);
         $user = $this->getDataGenerator()->create_and_enrol($course, 'student', ['firstname' => 'Zoe']);
 
         /** @var mod_forum_generator $generator */
@@ -349,6 +380,7 @@ final class forums_test extends core_reportbuilder_testcase {
 
         $forum = $generator->create_instance([
             'course' => $course->id,
+            'idnumber' => 'FORUM1',
             'name' => 'My forum',
             'intro' => 'My cool forum',
             'duedate' => $this->clock->time() + DAYSECS,