Greetings. Due to some errors which appear to be caused by missing plugins, I am searching for a way to list all available plugins in the context of ROS2 (a ROS1 solution is stated in pluginlibs ros wiki page).

The exact error is based on gazebo_ros2_control plugin:

[ERROR] [ros2_control_node-1]: process has died [pid 86933, exit code -6, cmd '/opt/ros/foxy/lib/controller_manager/ros2_control_node --ros-args --params-file /tmp/launch_params_3216bsip --params-file /home/developer/ROS_Foxy_ModProFT/install/modproft_ur_bringup/share/modproft_ur_bringup/config/sim_controllers.yaml --params-file /tmp/launch_params_9t9xm_16'].
[ros2_control_node-1] terminate called after throwing an instance of 'pluginlib::LibraryLoadException'
[ros2_control_node-1]   what():  According to the loaded plugin descriptions the class gazebo_ros2_control/GazeboSystem with base class type hardware_interface::SystemInterface does not exist. Declared types are  fake_components/GenericSystem test_hardware_components/TestSystemCommandModes test_hardware_components/TestTwoJointSystem test_system ur_robot_driver/URPositionHardwareInterface

The package containing said plugin is installed under /opt/ros/foxy/. But a listing would be helpful for debugging reasons.

Edit: I solved my problem. It seems that the gazebo_ros2_control plugin also starts the ros2_control node. Therefore, this wild plugin error appeared. I was not aware that gazebo_ros2_control was doing that. However the question still stands for the debugging of future errors.