diff -r b9456394d24f -r 86897f8a6598 src/java.desktop/share/classes/javax/swing/plaf/basic/BasicTabbedPaneUI.java
--- a/src/java.desktop/share/classes/javax/swing/plaf/basic/BasicTabbedPaneUI.java	Mon Jun 25 16:01:01 2018 +0530
+++ b/src/java.desktop/share/classes/javax/swing/plaf/basic/BasicTabbedPaneUI.java	Mon Jun 25 12:50:25 2018 +0530
@@ -606,6 +606,10 @@
         }
         mnemonicInputMap.put(KeyStroke.getKeyStroke(mnemonic, BasicLookAndFeel.getFocusAcceleratorKeyMask()),
                              "setSelectedIndex");
+        mnemonicInputMap.put(KeyStroke.getKeyStroke(mnemonic,
+                SwingUtilities2.setAltGraphMask(
+                        BasicLookAndFeel.getFocusAcceleratorKeyMask())),
+                "setSelectedIndex");
         mnemonicToIndexMap.put(Integer.valueOf(mnemonic), Integer.valueOf(index));
     }