We use Thickbox 3.1 for modal windows on our site and noticed recently that it has stopped loading on IE8. You can see the issue by going to http://alltrails.com and clicking "Login" on the top right. We've been trying unsuccessfully to troubleshoot but can't figure out how to resolve this. I'm hoping someone else has ran into this or knows Thickbox well and can offer a solution. Thanks in advance!
Are there any Javascript errors that show up in the F12 developer console?