Prep for colorization of fire

For the next colorize of fire to happen, we need the fire layer to have a black background.


Duplicate the background layer
Select the Background Layer,
Layer -> Duplicate Layer

Select the "FIRE" layer.
Layer -> Merge Down
- "FIRE" layer and "Background copy" layer gets merged together

-The new layer is called "Background copy".
Re-name it to "new FIRE" by double clicking on the word "Background copy"