HTML5中跨域属性的用途是什么？
官方规范将跨域属性声明为-
The crossorigin attribute is a CORS settings attribute. Its purpose is to allow images from third-party sites that allow cross-origin access to be used with canvas.
当它与CORS标头结合使用时，它将允许<img>元素定义的，从国外起源加载的图像用于画布。该过程就像从当前原点加载。
您可以使用它来解决JavaScript错误，例如记录js错误-
if (securityOrigin()->canRequest(targetUrl)) {
msg = myError;
line = myLineNumber;
source = sourceURL;
} else {
msg = "Error!";
source = String();
line = 0;
}