Queer signaling in the age of TikTok... There’s a new trending filter on TikTok called Blue & Red. Its job is simple: Like many others before it, the Blue & Red filter transforms your face either with stereotypically masculine features (against a blue background) or with feminine features (against a red background). The difference is that you can switch between the two simply by blinking, and it first went viral as a way to lip-sync to a specific duet from In the Heights between a male and female character. For some users, it became a whole lot more.