Apparatus and associated methods relate to a modular plug-in accessory including a connector for making pluggable electrical connection to a cascading electrical output port for providing cascading connection from an elongate light curtain, the accessory comprising an omni-directional light indicator to illuminate a light signal indicative of a status of the light curtain, wherein the accessory is configured to releasably make or break operative connection to the end cap containing the output port while the end cap is sealably connected to an end of the light curtain. In an illustrative example, the accessory may plug in directly to the terminal end of a light curtain. The receiving light curtain may be connected at the distal end of a string of light curtains. In some examples, the accessory may provide high visibility status indication information about any of the light curtain segments in the string of light curtains.