Select and Move all Events Without Bounding Box in Key Editor?

If I select a few events in the Key Editor I can move them around with no problems, and they appear as separate, unconnected events.

But, if I select all events in the part (for one track) either using ctrl-A or Edit>Select>All, I get a grey bounding box with a white edge, around all the events.

I find this makes it difficult to position the events in the editor.

Does anyone know why this is happening and if there’s a way to turn it off?

Thanks for any suggestions.