The Lower layers command lowers the selected
layers one position in the layer stack. If the selected layers already end
at the bottom of the stack, or if there is only one layer, this menu entry
is disabled.
7.20.1. コマンドの呼び出し方
You can access this command
From the main menu through
Layer → Stack → Lower Layers.
By clicking on the down-arrow icon at the bottom of the Layers dialog.
