https://github.com/FabricMC/fabric/blob/1.17/fabric-screen-api-v1/src/main/java/net/fabricmc/fabric/mixin/screen/ScreenMixin.java#L153

This is usually caused by the screen not calling super.init(Lnet/minecraft/client/MinecraftClient;II)V

The mentioned overload of init is final in 1.17, so its no longer possible to miss out the supercall, as the method cannot be overridden in the first place. The error is still useful though, I encountered it due to incorrect async code.
Additionally the error uses the name of the screen's superclass, rather than the name of the screen's class.