版本：
文件：
- https://cdn.bootcdn.net/ajax/libs/jschannel/1.0.0-git-commit1-8c4f7eb/jschannel.js
- https://cdn.bootcdn.net/ajax/libs/jschannel/1.0.0-git-commit1-8c4f7eb/jschannel.min.js
JSChannel is a small JavaScript abstraction layer on top of HTML5 cross-document messaging. It builds rich messaging semantics out of window.postMessage().