It sets the scale of waypoint pins, and of the stop mark inside them, at all zoom levels.
"s" is 0.75 × "m", and "l" is 1.25 × "m". WaypointsConfig.sizeFactor
multiplies whichever preset applies.
Available options:
"s" - Small icons"m" - Default medium icons"l" - Large icons
Route waypoint icon size preset.