def METHOD_NAME(geojson: dict,
                     crs_transformer: 'CRSTransformer',
                     to_map_coords: bool = False) -> dict:
    """Apply some basic transformations (listed below) to a GeoJSON.
    The following transformations are applied:
    1.  Removal of features without geometries.
    2.  Coordinate transformation to pixel coordinates.
    3.  Splitting of multi-part geometries e.g. MultiPolygon --> Polygons.
    4.  (Optional) If to_map_coords=true, transformation back to map
        coordinates.
    Args:
        geojson (dict): A GeoJSON-like mapping of a FeatureCollection.
        crs_transformer (CRSTransformer): A CRS transformer for coordinate
            transformation.
        to_map_coords (bool, optional): If True, transform geometries back to
            map coordinates before returning. Defaults to False.
    Returns:
        dict: Transformed FeatureCollection.
    """
    geojson = remove_empty_features(geojson)
    geojson = map_to_pixel_coords(geojson, crs_transformer)
    geojson = split_multi_geometries(geojson)
    geojson = simplify_polygons(geojson)
    if to_map_coords:
        geojson = pixel_to_map_coords(geojson, crs_transformer)
    if not all_geoms_valid(geojson):
        log.warning(f'Invalid geometries found in features in the GeoJSON.')
    return geojson