The reason was simple. Did you guess already?
Look at the example of problematic code below:
1 2 3
el = document.getElementById('copy_user_role_from'); url = url +'©_user_role_from='+ el.value; document.location.href = url;
Pay attention on the line #2. The source of problem was there at ‘©_’ characters.
Valid URL, as it is under Google Chrome and FireFox looks like:
Under Internet Explorer we have:
Thanks to Michael Wiekenberg for the help with isolating this issue.
Did you meet with similar unexpected behavior of so popular browser?