The quote tag can only be used 10 times in any post before breaking. Nesting does not seem to matter.
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Check out the "Politics, Science, and Religion" subforum and you'll see why. Also, it's not like this is the only quote bug, of course.
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You could always dual post.
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Do you really need to quote more than ten times in a post?
I've edited 3 posts from having too many quotes. Two of which I just ended up taking the quotes out entirely.
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