diff --git a/mod/assign/feedback/editpdf/classes/event/observer.php b/mod/assign/feedback/editpdf/classes/event/observer.php
index 278a694d5da..894ee73bb0e 100644
--- a/mod/assign/feedback/editpdf/classes/event/observer.php
+++ b/mod/assign/feedback/editpdf/classes/event/observer.php
@@ -51,6 +51,14 @@ class observer {
      * @param \mod_assign\event\base $event The submission created/updated event.
      */
     protected static function queue_conversion($event) {
+        $assign = $event->get_assign();
+        $plugin = $assign->get_feedback_plugin_by_type('editpdf');
+
+        if (!$plugin->is_visible() || !$plugin->is_enabled()) {
+            // The plugin is not enabled on this assignment instance, so nothing should be queued.
+            return;
+        }
+
         $data = [
             'submissionid' => $event->other['submissionid'],
             'submissionattempt' => $event->other['submissionattempt'],
diff --git a/mod/assign/feedback/editpdf/tests/feedback_test.php b/mod/assign/feedback/editpdf/tests/feedback_test.php
index a777955e95b..e7bab2a021e 100644
--- a/mod/assign/feedback/editpdf/tests/feedback_test.php
+++ b/mod/assign/feedback/editpdf/tests/feedback_test.php
@@ -578,4 +578,33 @@ class feedback_test extends \advanced_testcase {
         $conversions = \core_files\conversion::get_conversions_for_file($sourcefile, 'pdf');
         $this->assertCount(0, $conversions);
     }
+
+    /**
+     * Tests that when the plugin is not enabled for an assignment it does not create conversion tasks.
+     *
+     * @covers \assignfeedback_editpdf\event\observer
+     */
+    public function test_submission_not_enabled() {
+        $this->require_ghostscript();
+        $this->resetAfterTest();
+        cron_setup_user();
+
+        $course = $this->getDataGenerator()->create_course();
+        $student = $this->getDataGenerator()->create_and_enrol($course, 'student');
+        $assignopts = [
+            'assignsubmission_file_enabled' => 1,
+            'assignsubmission_file_maxfiles' => 1,
+            'assignfeedback_editpdf_enabled' => 0,
+            'assignsubmission_file_maxsizebytes' => 1000000,
+        ];
+        $assign = $this->create_instance($course, $assignopts);
+
+        // Add the standard submission.
+        $this->add_file_submission($student, $assign);
+
+        $task = \core\task\manager::get_next_adhoc_task(time());
+
+        // No task was created.
+        $this->assertNull($task);
+    }
 }