Tile grouping in the BDV 'slide out' side panel is lost when switching between "Multiview" and "Stitching" in the Stitching Explorer

[lollopus]

To replicate the issue:

1. Open a multi-tile dataset in BigStitcher
2. Open the slide-out side panel in the BDV window
3. Delete all 10 default groups
4. Drag and drop any number of tiles from the "Sources" section down to the "Groups" section; they will automatically be assigned to a new group
5. Expand the newly created group by clicking ">" to view the list of tiles it contains
6. Without closing the slide-out go to the BigSticher "Stiching Explorer" window and alternatively click "Stiching" and "Multiview"

RESULT: You should see that the new group is empied of all its tiles, except for one lonely tile

My conditions: MacOS Big Sur; Fiji/ImageJ 2.16.0/1.54r; Java 21.0.7; Latest BigStitcher build