OptionaladditionalAdditional custom layers to be added alongside the predefined ones.
Allows for further customization by specifying extra layers that complement the standard route visualization layers.
Use these if you want to add extra visuals to a specific module part, be it lines, symbols, or any MapLibre supported layer.
You can define 'beforeID' in the additional layers to place them under predefined ones (or other of your additional layers).
Configuration for adding custom layers to a map module based on its controlled source data.