A new version (/tmp/grub.uWvIeTmvSt) of configuration file /etc/default/grub is
available, but the version installed currently has been locally modified.

  1. install the package maintainer's version
  2. keep the local version currently installed
  3. show the differences between the versions
  4. show a side-by-side difference between the versions
  5. show a 3-way difference between available versions
  6. do a 3-way merge between available versions (experimental)
  7. start a new shell to examine the situation

What do you want to do about modified configuration file grub?