HPX-250 Viewfinder question

Through fat fingers hitting too many buttons on my HPX-250, I've added some function to my HPX250 that I can't figure out. There's a scene setting for flourescent, but that doesn't seem to turn this indicator on and off:



Does anyone know what the "FLUO" means, and where did it come from?

Thanks

Ryan Video Productions Inc. Rockaway, NJ