The quadrotot plugin.gazebo.xacro in hector_quadrotor_gazebo/urdf has a wired file name ending with .in
Maybe due to a wrong entry in the git ignore file in the repo.
That's intended. The actual file quadrotor_plugins.gazebo.xacro is generated by cmake depending on some compile time settings and availability of optional dependencies.
The quadrotot plugin.gazebo.xacro in hector_quadrotor_gazebo/urdf has a wired file name ending with .in Maybe due to a wrong entry in the git ignore file in the repo.