[ROS2 Foxy] [nav2] Map_saver crash when calling service /save_map

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Hello, I am working with ros2 foxy and nav2. I am using a map server to publish a static map for my global_costmap node. and I am also using a map_saver so I can call the service /map_saver/save_map whenever I need. This service is called in a python node with the following code : (The fill_map function is used to process the .pgm file created)

req = SaveMap.Request()
    req.map_topic = "/global_costmap/costmap"
    req.map_url = self.last_map
    req.image_format = "pgm"## Heading ##
    req.map_mode = "trinary"
    req.free_thresh = 0.1
    req.occupied_thresh = 0.65
    try:
      while not self.client_save_map.wait_for_service(timeout_sec=1.0):
        self.get_logger().info('service "save_map" not available, waiting again...')
      future = self.client_save_map.call_async(req)
      future.add_done_callback(self.fill_map)
      rclpy.spin_until_future_complete(self, future)
   except Exception as e:
     return 1

When this code calls the service to save the map I get the following error half the time :

[map_saver_server-15] [INFO] [1657705013.677320999] [map_saver]: Saving map from '/global_costmap/costmap' topic to 'map_20220713_113653' file
[map_saver_server-15] Magick: abort due to signal 11 (SIGSEGV) "Segmentation Fault"...
[ERROR] [map_saver_server-15]: process has died [pid 74196, exit code -6, cmd '/opt/ros/foxy/lib/nav2_map_server/map_saver_server --ros-args --params-file /tmp/launch_params_laosjfut --params-file /home/user/my_robot_application/install/my_robot/share/my_robot/config/nav2_params.yaml'].

So I looked at the mentionned file and nothing seemed wrong :

temp file :

 /**:
      ros__parameters:
        use_sim_time: true

config file (striped down to important nodes) :

global_costmap:
  global_costmap:
    ros__parameters:
      publish_frequency: 1.0
      update_frequency: 5.0
      global_frame: map
      robot_base_frame: base_link
      use_sim_time: False
      robot_radius: 0.5
      resolution: 0.05
      track_unknown_space: true
      plugins: ["static_layer", "obstacle_layer", "inflation_layer"]
      obstacle_layer:
        plugin: "nav2_costmap_2d::ObstacleLayer"
        enabled: True
        observation_sources: scan
        scan:
          topic: /scan
          max_obstacle_height: 2.0
          clearing: True
          marking: True
          data_type: "LaserScan"
      static_layer:
        plugin: "nav2_costmap_2d::StaticLayer"
        map_subscribe_transient_local: True
      inflation_layer:
        plugin: "nav2_costmap_2d::InflationLayer"
        cost_scaling_factor: 3.0
        inflation_radius: 0.55
      always_send_full_costmap: True
  global_costmap_client:
    ros__parameters:
      use_sim_time: False
  global_costmap_rclcpp_node:
    ros__parameters:
      use_sim_time: False

map_saver:
  ros__parameters:
    use_sim_time: False
    save_map_timeout: 15000
    free_thresh_default: 0.1
    occupied_thresh_default: 0.65

It seems to be a know issue (https://github.com/ros-planning/navig...) and to resolve it one must simply build from source magick but i can't figure out how to do it. I would greatly appreciate any direction as to where to search ? Thank you all for taking the time to read my question