Video subtitles not showing in offline/web exports

Hello all.

I have a developed a course that the client wants to use as both a SCORM object and a web object (distributed through a public website). The client has reported that the modules are not displaying video subtitles in the web version. I am able to replicate this behaviour when I export an offline version of the course.

Subtitles are in VTT format.

Please advise if this is a known issue and if there is anyway to fix this.

Hi @Mitch it certainly is a known issue for offline courses; if you go to Accessibility > Subtitles in the Media component you should see a warning to that effect:
screenshot of warning about subtitles not working in offline courses

It shouldn’t be a problem for the web version though. It certainly works fine for me:

If it’s not working for the customer then the most likely explanation is that their web server has not been configured to handle the vtt file type that web video subtitles use. They would need to check with the administrator of their web server that it has a mime-type of text/vtt mapped to the .vtt file extension.

Another possibility could be that - if you have sent them the ‘offline’ version of the course - they could be trying to run index.html either locally or from a file server and not via an actual web server. I’ve had a few instances in the past where a non-technical customer has not understood the difference between a file server and web server. Or has decided to test the course before uploading by simply extracting the files and double-clicking index.html

Thanks Matt. Very relieved it works ok for the web exports.

I wondered if they had taken the offline modules and uploaded them so that’s probably it.

The offline modules would still work if run from a web server - I did give that a quick test just in case but it still works fine and the subtitles display as expected.

The main difference between the ‘web’ and ‘offline’ versions is that in the web version all the course text content and configuration is loaded from .json files; in the offline version it’s loaded from a javascript file.

Ok, so if they are running them from a web server but the subtitles aren’t displaying it’s likely because of the mime-type issue (regardless of whether they grabbed the web or offline version of the files)?

That’s definitely the first thing I’d check, yes