diff --git a/mod/forum/classes/local/builders/exported_posts.php b/mod/forum/classes/local/builders/exported_posts.php
index ab459e85ad1..7f092e3bf5d 100644
--- a/mod/forum/classes/local/builders/exported_posts.php
+++ b/mod/forum/classes/local/builders/exported_posts.php
@@ -117,13 +117,15 @@ class exported_posts {
      * @param forum_entity[] $forums A list of all forums that each of the $discussions belong to
      * @param discussion_entity[] $discussions A list of all discussions that each of the $posts belong to
      * @param post_entity[] $posts The list of posts to export.
+     * @param bool $includeinlineattachments Whether inline attachments should be included or not.
      * @return stdClass[] List of exported posts in the same order as the $posts array.
      */
     public function build(
         stdClass $user,
         array $forums,
         array $discussions,
-        array $posts
+        array $posts,
+        bool $includeinlineattachments = false
     ) : array {
         // Format the forums and discussion to make them more easily accessed later.
         $forums = array_reduce($forums, function($carry, $forum) {
@@ -142,7 +144,10 @@ class exported_posts {
         $authorsbyid = $this->get_authors_for_posts($posts);
         $authorcontextids = $this->get_author_context_ids(array_keys($authorsbyid));
         $attachmentsbypostid = $this->get_attachments_for_posts($groupedposts);
-        $inlineattachments = $this->get_inline_attachments_for_posts($groupedposts);
+        $inlineattachments = [];
+        if ($includeinlineattachments) {
+            $inlineattachments = $this->get_inline_attachments_for_posts($groupedposts);
+        }
         $groupsbycourseandauthorid = $this->get_author_groups_from_posts($groupedposts);
         $tagsbypostid = $this->get_tags_from_posts($posts);
         $ratingbypostid = $this->get_ratings_from_posts($user, $groupedposts);
diff --git a/mod/forum/classes/local/exporters/post.php b/mod/forum/classes/local/exporters/post.php
index 6e821377c25..7137510e4e8 100644
--- a/mod/forum/classes/local/exporters/post.php
+++ b/mod/forum/classes/local/exporters/post.php
@@ -274,6 +274,7 @@ class post extends exporter {
                 'type' => $attachmentdefinition
             ],
             'messageinlinefiles' => [
+                'optional' => true,
                 'multiple' => true,
                 'type' => stored_file_exporter::read_properties_definition(),
             ],
diff --git a/mod/forum/externallib.php b/mod/forum/externallib.php
index 222612d84de..1f7e6157b5c 100644
--- a/mod/forum/externallib.php
+++ b/mod/forum/externallib.php
@@ -170,9 +170,10 @@ class mod_forum_external extends external_api {
      * @param   int $discussionid
      * @param   string $sortby
      * @param   string $sortdirection
+     * @param   bool $includeinlineattachments Whether inline attachments should be included or not.
      * @return  array
      */
-    public static function get_discussion_posts(int $discussionid, ?string $sortby, ?string $sortdirection) {
+    public static function get_discussion_posts(int $discussionid, ?string $sortby, ?string $sortdirection, bool $includeinlineattachments = false) {
         global $USER;
         // Validate the parameter.
         $params = self::validate_parameters(self::get_discussion_posts_parameters(), [
@@ -225,7 +226,7 @@ class mod_forum_external extends external_api {
         $legacydatamapper = mod_forum\local\container::get_legacy_data_mapper_factory();
 
         return [
-            'posts' => $postbuilder->build($USER, [$forum], [$discussion], $posts),
+            'posts' => $postbuilder->build($USER, [$forum], [$discussion], $posts, $includeinlineattachments),
             'forumid' => $discussion->get_forum_id(),
             'courseid' => $discussion->get_course_id(),
             'ratinginfo' => \core_rating\external\util::get_rating_info(
@@ -248,7 +249,9 @@ class mod_forum_external extends external_api {
         return new external_function_parameters ([
             'discussionid' => new external_value(PARAM_INT, 'The ID of the discussion from which to fetch posts.', VALUE_REQUIRED),
             'sortby' => new external_value(PARAM_ALPHA, 'Sort by this element: id, created or modified', VALUE_DEFAULT, 'created'),
-            'sortdirection' => new external_value(PARAM_ALPHA, 'Sort direction: ASC or DESC', VALUE_DEFAULT, 'DESC')
+            'sortdirection' => new external_value(PARAM_ALPHA, 'Sort direction: ASC or DESC', VALUE_DEFAULT, 'DESC'),
+            'includeinlineattachments' => new external_value(PARAM_BOOL, 'Whether inline attachments should be included or not', VALUE_DEFAULT,
+                false),
         ]);
     }
 
diff --git a/mod/forum/tests/externallib_test.php b/mod/forum/tests/externallib_test.php
index 5f0da6d5e4e..69fcb1e4805 100644
--- a/mod/forum/tests/externallib_test.php
+++ b/mod/forum/tests/externallib_test.php
@@ -593,7 +593,7 @@ class mod_forum_external_testcase extends externallib_advanced_testcase {
         );
 
         // Test a discussion with two additional posts (total 3 posts).
-        $posts = mod_forum_external::get_discussion_posts($discussion1->id, 'modified', 'DESC');
+        $posts = mod_forum_external::get_discussion_posts($discussion1->id, 'modified', 'DESC', true);
         $posts = external_api::clean_returnvalue(mod_forum_external::get_discussion_posts_returns(), $posts);
         $this->assertEquals(3, count($posts['posts']));
 
@@ -733,6 +733,81 @@ class mod_forum_external_testcase extends externallib_advanced_testcase {
         }
     }
 
+    /**
+     * Test get forum posts returns inline attachments.
+     */
+    public function test_mod_forum_get_discussion_posts_inline_attachments() {
+        global $CFG;
+
+        $this->resetAfterTest(true);
+
+        // Create a course and enrol some users in it.
+        $course = self::getDataGenerator()->create_course();
+
+        // Create users.
+        $user = self::getDataGenerator()->create_user();
+        $this->getDataGenerator()->enrol_user($user->id, $course->id);
+
+
+        // Set the first created user to the test user.
+        self::setUser($user);
+
+        // Create test data.
+        $forum = self::getDataGenerator()->create_module('forum', (object) [
+            'course' => $course->id,
+        ]);
+
+        // Create a file in a draft area for inline attachments.
+        $draftidinlineattach = file_get_unused_draft_itemid();
+        $draftidattach = file_get_unused_draft_itemid();
+        self::setUser($user);
+        $usercontext = context_user::instance($user->id);
+        $filepath = '/';
+        $filearea = 'draft';
+        $component = 'user';
+        $filenameimg = 'fakeimage.png';
+        $filerecordinline = [
+            'contextid' => $usercontext->id,
+            'component' => $component,
+            'filearea'  => $filearea,
+            'itemid'    => $draftidinlineattach,
+            'filepath'  => $filepath,
+            'filename'  => $filenameimg,
+        ];
+        $fs = get_file_storage();
+        $fs->create_file_from_string($filerecordinline, 'image contents (not really)');
+
+        // Create discussion.
+        $dummytext = 'Here is an inline image: <img src="' . $CFG->wwwroot .
+            "/draftfile.php/{$usercontext->id}/user/draft/{$draftidinlineattach}/{$filenameimg}" .
+            '" alt="inlineimage">.';
+        $options = [
+            [
+                'name' => 'inlineattachmentsid',
+                'value' => $draftidinlineattach
+            ],
+            [
+                'name' => 'attachmentsid',
+                'value' => $draftidattach
+            ]
+        ];
+        $discussion = mod_forum_external::add_discussion($forum->id, 'the inline attachment subject', $dummytext,
+            -1, $options);
+
+        $posts = mod_forum_external::get_discussion_posts($discussion['discussionid'], 'modified', 'DESC');
+        $posts = external_api::clean_returnvalue(mod_forum_external::get_discussion_posts_returns(), $posts);
+        $post = $posts['posts'][0];
+        $this->assertCount(0, $post['messageinlinefiles']);
+        $this->assertEmpty($post['messageinlinefiles']);
+
+        $posts = mod_forum_external::get_discussion_posts($discussion['discussionid'], 'modified', 'DESC',
+            true);
+        $posts = external_api::clean_returnvalue(mod_forum_external::get_discussion_posts_returns(), $posts);
+        $post = $posts['posts'][0];
+        $this->assertCount(1, $post['messageinlinefiles']);
+        $this->assertEquals('fakeimage.png', $post['messageinlinefiles'][0]['filename']);
+    }
+
     /**
      * Test get forum posts (qanda forum)
      */
@@ -2574,9 +2649,7 @@ class mod_forum_external_testcase extends externallib_advanced_testcase {
                         'wordcount' => null,
                         'author' => $exporteduser2,
                         'attachments' => [],
-                        'messageinlinefiles' => [
-                            0 => $this->get_expected_attachment($file1),
-                        ],
+                        'messageinlinefiles' => [],
                         'tags' => [],
                         'html' => [
                             'rating' => null,
@@ -2719,9 +2792,7 @@ class mod_forum_external_testcase extends externallib_advanced_testcase {
                         'wordcount' => null,
                         'author' => $exporteduser2,
                         'attachments' => [],
-                        'messageinlinefiles' => [
-                            0 => $this->get_expected_attachment($file2),
-                        ],
+                        'messageinlinefiles' => [],
                         'tags' => [],
                         'html' => [
                             'rating' => null,
@@ -3139,7 +3210,7 @@ class mod_forum_external_testcase extends externallib_advanced_testcase {
         $this->assertFalse(\mod_forum\subscriptions::is_subscribed($user->id, $forum, $discussion->id, $cm));
 
         // Get the post from WS.
-        $result = mod_forum_external::get_discussion_posts($discussion->id, 'modified', 'DESC');
+        $result = mod_forum_external::get_discussion_posts($discussion->id, 'modified', 'DESC', true);
         $result = external_api::clean_returnvalue(mod_forum_external::get_discussion_posts_returns(), $result);
         $found = false;
         foreach ($result['posts'] as $post) {