If course plugin image does not exists then use default image. see BT#10139

main/inc/lib/course_home.lib.php

@@ -853,10 +853,14 @@ class CourseHome
                 // Including Courses Plugins
                 // Creating title and the link
                 if (isset($tool['category']) && $tool['category'] == 'plugin') {
-                    $plugin_info = $app_plugin->get_plugin_info($tool['name']);
+                    $plugin_info = $app_plugin->getPluginInfo($tool['name']);
                     if (isset($plugin_info) && isset($plugin_info['title'])) {
                         $tool_name = $plugin_info['title'];
                     }
+
+                    if (!file_exists(api_get_path(SYS_CODE_PATH).'img/'.$tool['image'])) {
+                        $tool['image'] = 'plugins.png';
+                    }
                     $tool_link_params['href'] = api_get_path(WEB_PLUGIN_PATH).$tool['original_link'].'?'.api_get_cidreq();
                 }