According to the extended description:
Kaffeine is a media player for KDE. While it supports multiple Phonon
backends, its default backend is Xine, giving Kaffeine a wide variety of
supported media types and letting Kaffeine access CDs, DVDs, and
network streams easily.
Kaffeine used to support multiple backends, but Debian has only
supported xine for many years. Then Kaffeine moved to Phonon for version
1, but the switch was reversed before Kaffeine 1 was released, in
Kaffeine 1.0-pre3. Our package only offers Xine as backend since that
time, but the description was not updated.
By the way, I'm not sure that "for KDE" respects KDE's new terminology.
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