diff -r 11cb2d9413d4 -r 06170a0be62a src/main/java/de/uapcore/sudoku/DocumentHandler.java
--- a/src/main/java/de/uapcore/sudoku/DocumentHandler.java	Tue Jul 28 14:05:04 2020 +0200
+++ b/src/main/java/de/uapcore/sudoku/DocumentHandler.java	Tue Jul 28 14:27:14 2020 +0200
@@ -81,6 +81,7 @@
 
     /**
      * Saves the specified field to a file.
+     * On success, the modified state of all cells is set to false.
      *
      * @param field the field to save
      * @throws IOException if saving fails or the file name has not been set before
@@ -101,6 +102,7 @@
                 }
             }
         }
+        field.setAllCellsModified(false);
     }
 
     /**