To reproduce:
1.) Select an area with a ratio 1.5 for example.
2.) Save the selection ratio using "Edit > Selection ratio > Save selection as custom"
3.) Select an area with a different ratio (1.3 for example)
4.) Press 'C' to restore the user-defined selection ratio
--> Nothing happens (bug

5.) Choose "Edit > Selection ratio > Custom"
--> A selection is recalculated, but the selection is larger than the image (bug

If the bug in 5.) did not occur, press "Tab" to swap selection width & height
--> A selection is recalculated, but the selection is larger than the image (bug
