Set layer border
In
Screens / Aux.⚓
Select a layer.
In Properties, click Border to show the corresponding settings.
Toggle Edge to apply layer border settings.
Toggle Smooth to create a fading effect on the borders.
In Edge / Smooth, enter the hexadecimal color code or click the color preview to open the color picker.
Set the H size, V size and Opacity.
If needed, toggle Round to apply round corners settings and set the round corner radius.