However, even putting in the incorrect code you provided, the modules were just fine on both Chrome and Firefox.
Chrome:
Attachment 153698
Firefox:
Attachment 153699
So, I would conclude it is something else on your page that is causing the issue (perhaps another html module that has incorrect html also?) and that is why it is best if we could see the actual page. Run it through and html validator, then fix the issues, then see if it works.