Is there a script fu to puts a transparent layer behind the current layer? This would help me a lot and it would need to work on GIMP 3 RC1 as some script fu's do.

Can you tell me why you would need SCM to do this function when it's simple to just create a new transparent layer by just right clicking the layer , and selecting new layer then just lowering it.

Guess i am just curious.

I am guessing maybe so contrast_ can call it to do something GEGL filters operations on that.

To make the process faster. I'd studying how to do it myself.

I just solved the problem by making ctrl alt s lower layers and ctrl alt w raise layers

contrast_, would you prefer to have python plug-in so you can map it to one key?