F3+L Tints Top Block Faces Red at Light Level 7 or Below

For the purpose of certainty, efficiency, and precision regarding where hostile mobs are allowed to spawn in your Creative build, your makeshift Village, a community with multiple builders-

Top block faces that mobs can spawn on are slightly tinted red to indicate that a hostile mob can potentially spawn there.

The player could just eyeball it, light it up- large areas, that dark corner that looks lit- without having to check every block by walking over it.