Here’s a quick tip for managing panorama frames.
My own long-term practice has been to assign the green label to originals which are intended to be the component frames of panoramas, HDR, or other multi-frame techniques.I also stack them.
I do this as soon as possible after importing the files from the card. The risk I’m trying to avoid is that I might review one of these frames on its own and decide it’s a dud – badly composed/exposed – and delete it.
Green warns me that the frame is actually destined for stitching or whatever. That colour then carries over to the combined image, so I can then do smart collections by label and file type.