Some opencv Trackers dont appear to be implemented

I am using opencv 4.6.0 on Ubuntu22. There is sample code on using trackers that can be downloaded from A few of them dont appear to be implemented even though they appear in the docs. These are TrackerBoosting, TrackerMOSSE, TrackerTLD and TrackerMedianFlow. Are these implemented in some external module that needs to be included?

You must build opencv with opencv_contrib