You can modify the default desktop manager in raspbian with:
[root@dataBananaBerry:~]# update-alternatives --config x-session-manager
There are 5 options for alternative x-session-manager (that provides /usr/bin/x-session-manager).
Selecction Path Priority Status
------------------------------------------------------------
* 0 /usr/bin/startlxde 50 automatic mode
1 /usr/bin/lxsession 49 manual mode
2 /usr/bin/openbox-session 40 manual mode
3 /usr/bin/startlxde 50 manual mode
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