diff -r 11cb2d9413d4 -r 06170a0be62a src/main/java/de/uapcore/sudoku/ActionHandler.java
--- a/src/main/java/de/uapcore/sudoku/ActionHandler.java	Tue Jul 28 14:05:04 2020 +0200
+++ b/src/main/java/de/uapcore/sudoku/ActionHandler.java	Tue Jul 28 14:27:14 2020 +0200
@@ -129,7 +129,6 @@
             }
         }
         if (solver.check(field)) {
-            field.setAllCellsModified(false);
             try {
                 doc.save(field);
             } catch (IOException e) {