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^{[possible bug?]}

[edit] Documentation

designates a statement as a potential or confirmed bug. When used with no parameters ({{bug}}), prints ^{[possible bug?]} and automatically adds the page to the category Possible bugs. If the "confirmed" parameter = yes ({{bug|confirmed=yes}}), then prints ^{[confirmed bug]} instead. If the url parameter is specified, the text will also link to the url specified ({{bug|confirmed=yes|url=http://bugs.developers.facebook.com/show_bug.cgi?id=93}} → ^bug).