I am working with SystemJS and I have a pseudo-bootstrapper file that I use to check to make sure certain conditions are met before the loading of the main scripts to execute the page load. Here is a snippet of that code.
var obj = document.createElement('script');
obj.src = 'jspm_packages/system.js';
document.body.appendChild(obj);
This code does NOT execute the script, yet it does load it with a 200 code as evidenced by the network tab within the IE dev tools. There should be a global object "System" created, but it does not exist. Looking through the DOM, the object is properly created and appended to the body.
Does anyone know if this is strictly an issue with IE and SystemJS? I have no idea what's going on. I'm pulling my hair out, as per usual with the demon that is IE. I should note that every other browser works as expected, providing the "System" global variable.
EDIT Further testing has assured that this is not an issue with appendChild, as other scripts using the same method, execute on load just fine.
The answer is that IE versions < Edge do not support promises. I needed a polyfill for IE 11.