[xmonad] XMonad.Hooks.ManageDocks: can't toggle dock gap since 0.13

[Mekeor Melire]

Hello,

since version 0.13 of xmonad(-contrib) and upgrading my config to that
version, I find my config not to work as expected. Specifically, my
binding for `sendMessage ToggleStruts` doesn't toggle the dock gap
anymore. Instead, all windows overlap over my dock (dzen2) all the time.

I followed the instructions at the documentation (of
XMonad.Hooks.ManageDocks at xmonad-contrib):

    https://hackage.haskell.org/package/xmonad-contrib-0.13/docs/XMonad-Hooks-ManageDocks.html

i.e. I apply `docks` on the XConfig and `avoidStruts` on the layout.

You can find my current config on GitHub (repo: "config"; branch:
"xmonad-0.13"):

    https://github.com/mekeor/config/blob/xmonad-0.13/home/mekeor/.xmonad/xmonad.hs

I also checked CHANGES.md but version 0.13 only seems to fix bugs in
that module.

What am I doing wrong? Am I missing something?

--
mekeor ~ EDD3 DFFA 76F6 11C0 145F 9A99 AC85 BAD8 A2F8 C868