Continuity: When Lily is approached by the girl that's been sabotaging Barney while he's trying to pick up girls, the girl's hair is wavy/curly - and her voice definitely not
Britney Spears. Later we find out that the girl who talked to Lily was Abby, Britney's character, and the scene is shown again - this time with the actual Britney in it, straight hair and all.
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