It looks like a timing issue. I would suggest to add a test on incubator between
var incubator = dojo.query('.mx-incubator')[0];
this.observeDOM( incubator, dojo.hitch(this, this.checkReload), false);
you can test this by changing the widget code in the deployment folder. Don't forget to change the widget if this solves it and suggest a change in github. https://github.com/appronto/UXManipulator/blob/master/UXManipulator/UXManipulator.js
Edit 1:
Leave the ie stuff in. I mean
var incubator = dojo.query('.mx-incubator')[0];
if (incubator) {
this.observeDOM( incubator, dojo.hitch(this, this.checkReload), false);
}
This appears to be working now. Not exactly sure why. I noticed the widget was working on a different page, so copied that widget to the problem page and it's working now.