boolean canRestoreSelection() {
            if ( previousRestoreSelection == null || previousRestoreSelection.isEmpty() ) {
                return false;
            }
            
            if ( previousRestoreSelection.equals( activeSelection ) ) {
                return false;
            }
            
            
            return true;
        }
A state class to keep track of past and current selections and to determine when we can
restore an old selection.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/select/RestoreSelectionPlugin.java