Closed Captioning feature allows you to upload a .vtt file (similar to a regular subtitle file type) and during the webinar attendees will be able see the closed captioning by simply toggling this CC button.
To upload a web vtt file, you can go to the Miscellaneous menu in your webinar editor
And then scroll down until you find Closed Captioning (note this feature will not be available for live or hybrid webinars).
Click on the Configure button, and then select the web vtt file from your computer, and then hit save.
Once you do that, you can preview your webinar to see the CC in action.
How to Make a web vtt File:
Please note, StealthSeminar support does not offer a transcription service.
Here are some resources on how to make/create a web vtt file from scratch:
How to convert a .srt file to web vtt file:
If you do not have a web vtt file, and instead have a srt file, then you can go to any of these websites, simply upload the srt file and they will automatically convert your srt file for free.