reading the source code, setting NOSSN to 1 _disables_ session support,
not enable it.
O_NERD := 0 # support icons-nerdfont
O_QSORT := 0 # use Alexey Tourbin's QSORT implementation
O_BENCH := 0 # benchmark mode (stops at first user input)
-O_NOSSN := 0 # enable session support
+O_NOSSN := 0 # disable session support
O_NOUG := 0 # disable user, group name in status bar
O_NOX11 := 0 # disable X11 integration