Yes it will function with shaders if the shader maintains the vanilla lightmap. Otherwise the shaders will simply override the darkness. Don't worry though, the handheld candle and flashlight will still work!

Candles last much longer than flashlights but are harder to see with.

Flashlights die quicker than candles but are brighter. - They can also be recharged in the sunlight on an item frame or in the player's hand..

They can be recharged in the sunlight on an item frame or in the player's hand.

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