版本：
文件：
- https://cdn.bootcdn.net/ajax/libs/webvtt-parser/2.2.0/html-entities.json
- https://cdn.bootcdn.net/ajax/libs/webvtt-parser/2.2.0/parser.js
- https://cdn.bootcdn.net/ajax/libs/webvtt-parser/2.2.0/parser.min.js