When working with thousands of markers it can extremely difficult to place the first couple of markers.
If my photo alignment is done without georeferencing the markers might not even be visibly in the photos.
Normally I would go into a photo, right click on a place where I would like to set a marker, click on "Place marker" and select the corresponding marker.
If I have thousands of markers only the first few markers, which can fit inside the monitor will be shown and if my marker is not within the few shown, I cannot place it.
What I am suggesting is a way to select a marker in the list on the left, right click it (or similar) select "place in photo" and the go into a photo and click where I would like to set it.