These are mostly a rehash of the instructions in MDL-40477 , but submodules should now be correctly pathed: Note: You must check this with both jsrev = -1; and jsrev unset in your config file. Note: Have your JS console open for ALL testing here and be on the look out for any related errors Generally check pages in Moodle Confirm that there were no (new) JS errors on the page Confirm that there all JS was correctly loaded by the YUI loader Check the results of calls to theme/yui_combo.php Confirm that the results had content In the JS console run a few additional calls and check that the output in the Network console is appropriate: YUI().use('MODNAME'); where modname is in: moodle-core-notification moodle-core-chooserdialogue moodle-course-modchooser moodle-calendar-eventmanager moodle-calendar-eventmanager-skin And the following should be retrieved with an appropriate path (though no content yet): moodle-core-notification-withsubmodule moodle-core-notification-withsubmodule-skin Note, appropriate path should be in the format: http://tangerine.local/moodle/theme/yui_combo.php?moodle/-1/core/notification/notification-withsubmodule-debug.js http://tangerine.local/moodle/theme/yui_combo.php?moodle/1372617447/core/notification/notification-withsubmodule-min.js http://tangerine.local/moodle/theme/yui_combo.php?moodle/-1/core/notification/notification-withsubmodule.css http://tangerine.local/moodle/theme/yui_combo.php?moodle/1372617447/core/notification/notification-withsubmodule.css