After renaming a Menu, in order to display it, we need to change and re-save 'Menu Display Location'

• Create 'Menu.Test'
• Use 'Menu Display Location' = 'Inside a Right Panel'
• Go to Administration and set 'Panels Display on the Left' with 'Menu.Text'

• ---

• Rename 'Menu.Test' to 'Menu.Test1'
• Go to Administration and change 'Panels Display on the Left' to 'Menu.Text1'

• ---

• Refresh: Nothing happen
• Go to 'Menu.Text1':
  • Resave : Nothing Happen
  • Change 'Menu scope visibily', Resave: Nothing Happen
  • Change 'Menu Display Location', Resave: Works

In order for the renamed page to be displayed in the panel, we need to make the modification to the extensionPointID and resave.