A new version of configuration file /etc/default/grub is available, but the version installed   │
  │ currently has been locally modified.                                                            │
  │                                                                                                 │
  │ What do you want to do about modified configuration file grub?                                  │
  │                                                                                                 │
  │                   install the package maintainer's version                                      │
  │                   keep the local version currently installed                                    │
  │                   show the differences between the versions                                     │
  │                   show a side-by-side difference between the versions                           │
  │                   show a 3-way difference between available versions                            │
  │                   do a 3-way merge between available versions (experimental)                    │
  │                   start a new shell to examine the situation                                    │
  │                                                                                                 │
  │                                                                                                 │
  │                                             <Ok>