A new Moodle instance installed as a Plesk Application opens with a broken css/js.
The following error is displayed in the web browser console:
Mixed Content: The page at 'https://example.com/' was loaded over HTTPS, but requested an insecure script 'http://example.com/theme/yui_combo.php?rollup/3.17.2/yui-moodlesimple-min.js'. This request has been blocked; the content must be served over HTTPS.
wwwroot is set to use the HTTP protocol:
http://example.com in Moodle configuration file config.php and Permanent SEO-safe 301 redirect from HTTP to HTTPS is enabled in Plesk.
This issue has been reported as bug #APSI-1566 which will be fixed in a future update.
Until the issue is resolved, apply the following workaround:
Go to Domains > example.com > File manager > httpdocs > config.php and change the HTTP protocol to HTTPS for
$CFG->wwwroot = 'http://example.com';
$CFG->wwwroot = 'https://example.com';