You could always make something that closes unclosed quotes within HTML brackets, although I suppose that would be a lot of work. It would probably be more effort than it's worth.
I think I see what causes the favorites list deletion problem: in Mozilla (and perhaps Netscape and others that I haven't tested it in), whenever I don't close an ending quote in HTML in my profile, it seems to subsequently think that the following block of HTML for "Display E-Mail" and "Favorites" is part of my profile. When I delete that HTML to revert my profile back to normal, every time I've done that my favorites list gets deleted.
This problem does not appear to happen in Internet Explorer, likely due to its better ability to successfully parse badly formed HTML; that ability results in those two following sections not being included in your profile and your favorites list staying intact.
I'm not really sure if that would be fixable (unless you did my first suggestion above); it seems to me like it's inherent in how Mozilla renders the HTML. I'm just answering your question as to why that deletion happens.
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