Player and SSL
The player works without problems on the secure HTTPS protocol, if all requests for text files go in the same way. This applies to streams in DASH or HLS, or playlists in txt format. For advertisings the player corrects links by itself, since ad networks always support a secure connection.
So, if the builder, or your site is open through HTTPS, then the link to the m3u8 file (HLS manifest) should also be with HTTPS. If the server that sends this text file does not have an SSL certificate, then the player will not be able to download it due to browser security restrictions.
What to do?
Make sure that this file can be downloaded using the HTTPS protocol. You can install a free SSL certificate using this service.
If this is not possible, switch the builder into HTTP mode (change it in the address bar from https://playerjs.com to http://playerjs.com). The site on which you install the player must also be opened only via HTTP. We do not recommend this option, since HTTPS becomes an indispensable standard and sooner or later you will have to go to it.