By analyzing captured packets, I obtained the addresses for retrieving video subtitles. Could you please explain where these subtitle addresses come from? Does Apple provide official documentation on this?

[chunxige]

[insidegui]

The addresses are found in the feeds used by the Apple Developer app.

The main URL changes when there are major updates, but the current config is located at https://devimages-cdn.apple.com/wwdc-services/vu4edl84/0D767836-D0F9-4343-B7AE-98B2A3E725B5/config.json