in idea-plugin/src/main/java/com/jetbrains/ide/streamdeck/keymap/ActionsTree.java [441:449]
public static Icon getEvenIcon(Icon icon) {
LayeredIcon layeredIcon = new LayeredIcon(2);
layeredIcon.setIcon(EMPTY_ICON, 0);
if (icon != null && icon.getIconHeight() <= EMPTY_ICON.getIconHeight() && icon.getIconWidth() <= EMPTY_ICON.getIconWidth()) {
layeredIcon
.setIcon(icon, 1, (-icon.getIconWidth() + EMPTY_ICON.getIconWidth()) / 2, (EMPTY_ICON.getIconHeight() - icon.getIconHeight()) / 2);
}
return layeredIcon;
}