If a first snapshot is taken, then some elements are changes (3D layers (de)activated, background images (un)selected, colors changed,...), a new snapshot does take into account all these changes: it is "freezed" in the previous configuration.
The only way to reinitialize the snapshot is to refresh the whole page, but then all custom display (color, zoom, orientation) are lost.
If a first snapshot is taken, then some elements are changes (3D layers (de)activated, background images (un)selected, colors changed,...), a new snapshot does take into account all these changes: it is "freezed" in the previous configuration. The only way to reinitialize the snapshot is to refresh the whole page, but then all custom display (color, zoom, orientation) are lost.