This seems to be an issue with Content-Security Policy applied; can you use the "Inspect element - Console" of Ifrefox (or other developer tools if you use other browser) to check if there is any error?
In this version I have done an important change to make the extension fully compliant with CSP and Joomla! coding standards. For some reason you and the other user who started this forum are not loading resources. Working on it. I will contact you if I find the reason.