[Solved] What is the zero index in getElementsByTagName?
var js = document.createElement(‘script’); js.src=”https://stackoverflow.com/questions/45500080/myscript.js”; document.getElementsByTagName(‘head’)[0].appendChild(js); You get all head elements (there should be only one) and you add the script there so the result is <html> <head> <script> … if there’s no head in the document, most browsers will create the head element even if the tag is not there. Have a look at … Read more