I haven’t seen this captured anywhere, and not sure if this right place to highlight this change to OH3 but the GPSTracker binding has had what I view as a significant and breaking change in moving from OH2 to OH3. In OH3 the regionTrigger Channel no longer allows for Linking of an Item to the Channel from the UI and the regionTrigger must be incorporated in a rule to determine if the person is entering or leaving the Region. In OH2 this was handled through binding and no rule was required for the tracker to work. The release notes for OH3 do not mention this or any changes affecting GPSTracker, implying everything works as in OH2. Further the GPSTracker documents also do not include this change. The only tip I found is the notation on the regionTrigger Channel. Its left to the user to figure out the rest. Probably not the best idea, especially for a new user.
Here is an example based on the item Link I created for myself which seems to be working for me. In this example “EX” is the unique OWNTracks ID and “Home” is the regionName as defined by the user in the System Distance Channel of the GPSTracker Binding. The Item vGPSTrackerEX_RegionTrigger is a SwitchType Item that is defined in Text file and is manually Linked to regionTracker Channel so that it can be used to signal when EX is in the Home region (ON) or outside of the Home region (OFF)
.items
Switch vGPSTrackerEX_RegionTrigger "EX OWNTRacker Presence [MAP(own_tracks.map):%s]" <man_3> {channel="gpstracker:tracker:ex:regionTrigger" [profile="gpstracker:trigger-geofence", regionName="Home"]} // OWN Tracker