Question about using external library

Just curious, is it allowed on GreasyFork to inject external library as what it is done in this script?

//注入JS：jquery
function injectJs(e) {
if (e.jQuery) {
log('jquery available');
} else {
var ele = e.document.createElement('script');
ele.src = "https://cdn.staticfile.org/jquery/1.12.4/jquery.min.js";
e.document.body.appendChild(ele);
var id = e.setInterval(function () {
if (e.jQuery) {
e.clearInterval(id);
}
}, 100);
}
}

已移除，是历史代码。按道理讲，是不推荐直接注入的。