Index: src/org/openstreetmap/josm/gui/io/ActionFlagsTableCell.java
===================================================================
--- src/org/openstreetmap/josm/gui/io/ActionFlagsTableCell.java	(revision 17307)
+++ src/org/openstreetmap/josm/gui/io/ActionFlagsTableCell.java	(working copy)
@@ -34,6 +34,10 @@
  * <br>col.setCellRenderer(aftc);
  * <br>col.setCellEditor(aftc);
  * </code>
+ *
+ * Note: Do not use the same object both as <code>TableCellRenderer</code> and
+ * <code>TableCellEditor</code> - this can mess up the current editor component
+ * by subsequent calls to the renderer (#19995 and #12462).
  */
 class ActionFlagsTableCell extends JPanel implements TableCellRenderer, TableCellEditor {
     private final JCheckBox[] checkBoxes = new JCheckBox[2];
Index: src/org/openstreetmap/josm/gui/io/SaveLayersTableColumnModel.java
===================================================================
--- src/org/openstreetmap/josm/gui/io/SaveLayersTableColumnModel.java	(revision 17307)
+++ src/org/openstreetmap/josm/gui/io/SaveLayersTableColumnModel.java	(working copy)
@@ -108,12 +108,13 @@
         addColumn(col);
 
         // column 2- actions to take
-        ActionFlagsTableCell aftc = new ActionFlagsTableCell();
+        ActionFlagsTableCell aftcRenderer = new ActionFlagsTableCell();
+        ActionFlagsTableCell aftcEditor = new ActionFlagsTableCell();
         col = new TableColumn(2); // keep in sync with SaveLayersModel#columnActions
         col.setHeaderValue(tr("Actions To Take"));
         col.setResizable(true);
-        col.setCellRenderer(aftc);
-        col.setCellEditor(aftc);
+        col.setCellRenderer(aftcRenderer);
+        col.setCellEditor(aftcEditor);
         col.setPreferredWidth(100);
 
         addColumn(col);