[xmonad] recompiling xmonad.hs results in one virtual screen instad of two

[Christopher J. Ruwe]

I am using xmonad with two screens managed by xrandr with

xrandr --output HDMI1 --mode 1920x1080 --pos 0x0 --rotate normal \
       --output LVDS1 --off \
       --output DP2 --off \
       --output DP1 --off \
       --output VGA1 --mode 1920x1080 --pos 1920x0 --rotate normal

I am using a xmonad setup from last year's december and screens 1 - 9
are placed on single physical screens.

A minor readaption of this setup (window size only) resulted in xmonad
treating the two screens as one virtual screen. Investigating, I
found out that just recompiling the very same .xmonad.hs resulted in
the same change.

I supsect some of imports have changed, which results in this
behaviour.

I import

import XMonad
import System.Exit

import qualified XMonad.StackSet as W
import qualified Data.Map        as M

import XMonad.Hooks.ManageDocks
--import XMonad.Hooks.EwmhDesktops

import XMonad.Layout.Maximize
import XMonad.Layout.GridVariants as GV
import XMonad.Layout.MultiColumns
import XMonad.Layout.PerWorkspace 

Regrettably, I have deleted all last year's binaries three weeks ago,
so I cannot recursively diff and I have not found similar reports in
the archives. For now, I copied a xmonad.o from a zfs-snap, but I
would like to change my config in the future. Can somebody help me?

Thanks and cheers, 
-- 
Christopher 
TZ:         GMT + 2h
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