debug info

dpkg -l gnome-session-xmonad

Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name                                           Version                      Architecture                 Description
+++-==============================================-============================-============================-==================================================================================================
ii  gnome-session-xmonad                           1.0-1xenial1                 all                          GNOME Session Manager - XMonad session

ps (after)

[christian@christian-thinkpad ~]$ ps -aux | grep xmonad
christi+  4955  0.0  0.1 707224 17164 ?        Ssl  09:45   0:00 /usr/lib/gnome-session/gnome-session-binary --session=gnome-xmonad
christi+  5018  0.1  0.0  59732  8472 ?        S    09:45   0:03 /home/christian/.xmonad/xmonad-x86_64-linux
christi+  9951  0.0  0.0  14228  1100 pts/1    S+   10:17   0:00 grep --color=auto xmonad

[christian@christian-thinkpad ~]$ ps -aux | grep gnome-session
christi+  4955  0.0  0.1 707224 17164 ?        Ssl  09:45   0:00 /usr/lib/gnome-session/gnome-session-binary --session=gnome-xmonad
christi+  4970  0.0  0.0 206984  6744 ?        Sl   09:45   0:00 /usr/lib/at-spi2-core/at-spi2-registryd --use-gnome-session
christi+  9956  0.0  0.0  14228   896 pts/1    S+   10:17   0:00 grep --color=auto gnome-session

ps (before)

[christian@christian-thinkpad ~]$ ps -aux | grep xmonad
christi+ 12551  1.1  0.1 698640 14644 ?        Ssl  10:20   0:00 /usr/lib/gnome-session/gnome-session-binary --session=gnome-xmonad
christi+ 12774  0.2  0.0  59428  8072 ?        S    10:20   0:00 /home/christian/.xmonad/xmonad-x86_64-linux
christi+ 12875  0.0  0.0  14228   980 pts/3    S+   10:21   0:00 grep --color=auto xmonad
[christian@christian-thinkpad ~]$ ps -aux | grep gnome-session
christi+ 12551  0.7  0.1 698640 14644 ?        Ssl  10:20   0:00 /usr/lib/gnome-session/gnome-session-binary --session=gnome-xmonad
christi+ 12566  0.1  0.0 206984  6684 ?        Sl   10:20   0:00 /usr/lib/at-spi2-core/at-spi2-registryd --use-gnome-session
christi+ 12880  0.0  0.0  14228   968 pts/3    S+   10:21   0:00 grep --color=auto gnome-session

xmonad.errors

xmonad.hs:30:1: Warning: Tab character

xmonad.hs:44:27: Warning:
    In the use of ‘defaultConfig’
    (imported from XMonad, but defined in XMonad.Config):
    Deprecated: "Use def (from Data.Default, and re-exported by XMonad and XMonad.Config) instead."

xmonad.hs

import XMonad
import XMonad.Config.Gnome
import XMonad.Layout.Minimize
import qualified Data.Map as M
import System.Exit -- exitWith
import XMonad.Layout.Fullscreen
import XMonad.Layout.NoBorders
import XMonad.Layout.Gaps
-- Fullscreen imports:
import XMonad.Hooks.ManageHelpers
import XMonad.Hooks.SetWMName
import qualified XMonad.StackSet as W
import Control.Monad
import Data.Monoid (All (All))

{-
# Unity flavor sources:
http://www.haskell.org/haskellwiki/Xmonad/Using_xmonad_in_Unity_2D
http://markhansen.co.nz/xmonad-ubuntu-oneiric/
https://gist.github.com/1300108
-}

--myLayout = minimize (Tall 1 (3/100) (1/2)) -- ||| Full
--unityLayout = gaps [(U, 24)] $ layoutHook gnomeConfig
unityLayout = gaps [(U, 24)] (layoutHook gnomeConfig) 
          ||| noBorders (fullscreenFull Full)

myKeys conf@(XConfig {XMonad.modMask = modm}) = -- M.fromList $ -- comment M.fromList when using 'newKeys'
             [ 
	       ((modm , xK_Escape)          , kill)
         , ((modm , xK_s)               , spawn $ XMonad.terminal conf)
         , ((modm,               xK_space ), sendMessage NextLayout) -- %! Rotate through the available layout algorithms
         , ((modm .|. shiftMask, xK_space ), setLayout $ XMonad.layoutHook conf) -- %!  Reset the layouts on the current workspace to default
         , ((modm , xK_x)               , spawn "chrome")
         , ((modm , xK_d)               , spawn "nautilus")
         , ((modm , xK_a)               , spawn "gnome-system-monitor")
         , ((modm .|. shiftMask , xK_d) , spawn "killall nautilus; nautilus")
         , ((modm .|. shiftMask , xK_Delete) , spawn "gnome-session-quit --reboot")
         , ((modm .|. shiftMask , xK_End) , spawn "gnome-session-quit --power-off")
--               ((modm, xK_s)              , withFocused (\f -> sendMessage (MinimizeWin f)))
--             , ((modm .|. shiftMask, xK_s), sendMessage RestoreNextMinimizedWin)
             ]

newKeys x = M.union (keys defaultConfig x) (M.fromList (myKeys x))

main = do
  xmonad $ gnomeConfig
    { terminal    = "gnome-terminal"
    , modMask     = mod4Mask
--    , doFloat     = ["Evince", "Totem"]
    , focusFollowsMouse = False
    , borderWidth = 2
    , normalBorderColor  = "#4D4B45"
    , focusedBorderColor = "#DD0F0F" -- "#00FF00" -- terminal green -- "#A6E1FF" -- "green"
--    , layoutHook = noBorders Full
--    , layoutHook  = myLayout
    , layoutHook = unityLayout
    , startupHook = setWMName "LG3D" -- Fixes Intellij Idea https://bbs.archlinux.org/viewtopic.php?id=95437
    , keys        = newKeys
--    , keys        = myKeys
    , manageHook = unityManageHook
    }

unityManageHook = composeAll (
    [ manageHook gnomeConfig
    , className =? "Unity-2d-panel" --> doIgnore
--    , className =? "Unity-2d-launcher" --> doFloat
    , className =? "Unity-2d-launcher" --> doIgnore
    ])

xsession-errors

openConnection: connect: No such file or directory
cannot connect to brltty at :0
upstart: indicator-application main process ended, respawning
upstart: indicator-application main process ended, respawning
upstart: indicator-application respawning too fast, stopped