Bug using span tag.
Q: How long can cat live?
Show correct answer This text should be displayed only once! (my copy above is ghost! can't select or do anything)

But using div tag is all ok
Q: How long can cat live?
Show correct answer This text should be displayed only once!

In Opera 7.x you see text "This text should be displayed only once!" twice using span tag, but should be displayed only once. If the init value of visibility of span is visible, not hidden, than it's all right.
In Opera 6.x all after first br tag in span tag isn't displayed after clicking on "Show correct answer".
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