[gentoo-user] package.use update

[Mick]

Did you see this today?
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# etc-update 
Scanning Configuration files...
The following is the list of files which need updating, each
configuration file is followed by a list of possible replacement files.
1) /etc/portage/package.use (1)
Please select a file to edit by entering the corresponding number.
              (don't use -3, -5, -7 or -9 if you're unsure what to do)
              (-1 to exit) (-3 to auto merge all remaining files)
                           (-5 to auto-merge AND not use 'mv -i')
                           (-7 to discard all updates)
                           (-9 to discard all updates AND not use 'rm -i'): 1

File: /etc/portage/._cfg0000_package.use
1) Replace original with update
2) Delete update, keeping original as is
3) Interactively merge original with update
4) Show differences again
Please select from the menu above (-1 to ignore this update):
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What is it about?
-- 
Regards,
Mick