With Canonical is developing Mir, a new display server and making it default in Ubuntu 13.10, other Ubuntu derivatives are faced with the difficulty to port their desktop environments to the new display server. As its a lot of work, and the first editions of Mir not that promising, Kubuntu and Lubuntu have decided to drop Mir as their display server in 13.10.
July 1, 2013
Lubuntu, Kubuntu 13.10 May Not Use Mir As Their Display Server
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