[Morpheus]

Differences between 7z, 7za and 7zr binaries The package includes three binaries, /usr/bin/7z, /usr/bin/7za, and /usr/bin/7zr. Their manpages explain the differences: 7z uses plugins to handle archives. 7za is a stand-alone executable. 7za handles fewer archive formats than 7z, but does not need any others. 7zr is a stand-alone executable. 7zr handles fewer archive formats than 7z, but does not need any others. 7zr is a "light-version" of 7za that only handles 7z archives.

p7zip - ArchWiki
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