Lightroom develop settings lost after roundtrip to Photoshop

You stated “ edit original in PS”

So.

1. You are not working with a RAW  file, correct?

2. You did not select edit WITH Lightroom adjustments.

So, you wind up editing in PS the JPEG ot TIFF that you started with in LRC, without any LRC edits. Accomplish some PS edits, And save or close. LRC then shows that very image with the PS edits, but none of the older LRC edits.

LRC did exactly what you told it to do. It send the photo to PS without any edits. PS did exactly what would be expected fir a non RAW photo, it did not work on an temporary image, it worked on the actual image, And when you finished PS sent that edited image back to LRC as is, not as a copy. LRC then did exactly as expected, nothing folder management wise, it did not have to add the photo to the catalog, as this is the same file, LRC did not and would not reapply the old LRC edits to the photo, they are gone.

I think you selected the wrong option at edit in.

I also am not sure what is 'lost' from the Question.

This is what I see (in screen-clips)-

1. JPG Image in Lightroom-Classic

2. Apply some edits in Lightroom-  Desaturate all 'Greens'

3. Open in Photoshop "as Original" - (Color returns to green -as in the 'original' to be expected)

4. Do some Spot Healing to remove the flower bud-

5. Save and Return to Lightroom-

Note that the 'Desaturations' done previously in Lightroom are still visible. The Ps edits are still visible.

I am curious to know if the OPs workflow is more complex.

See this post for three workarounds to this longstanding bug. Add your constructive opinion, and be sure to click Me Too and Follow in the upper-right corner of that bug report. That will make it a little more likely Adobe might prioritize a fix, and you'll be notified when the bug's status changes.

What edits are lost, Lightroom or Photoshop edits? When you send a file to Photoshop the Lightroom edits are applied to a new file. When you save the new file and return to Lightroom you should see any edits you made in Photoshop, but all Lightroom settings will be at the default starting points.