Fix fullscreen

README.md

@@ -18,10 +18,16 @@ and indicators.
 Recent Ubuntu releases support this requirement *almost* out of the box, thanks
 to a dedicated GNOME Flashback session that uses xmonad as the window manager.
 However, with an empty configuration, you won't have panels. With the default
-`XMonad.Config.Gnome`, many keybindings won't work properly due to conflicts
-with GNOME keybindings or bugs. So I thought I'd put together a curated minimal
-xmonad config that fixes these issues but otherwise gives you a clean slate to
-add your own favorite configuration options.
+`XMonad.Config.Gnome`, there are still some unacceptable problems:
+
+* Many keybindings won't work properly due to conflicts with GNOME keybindings
+  or bugs.
+* Applications going fullscreen (like media players or browsers) is not
+  supported.
+
+So I thought I'd put together a curated minimal xmonad config that fixes these
+issues but otherwise gives you a clean slate to add your own favorite
+configuration options.
 
 Setup
 -----

xmonad.hs

@@ -1,13 +1,46 @@
 import XMonad
 import XMonad.Config.Gnome
+import XMonad.Hooks.EwmhDesktops
+import XMonad.Hooks.SetWMName (setWMName)
 import XMonad.Util.EZConfig
 import XMonad.Util.Run
 
 main = xmonad $ gnomeConfig {
     -- Use Win key rather than Alt. Alt is used by GNOME for many things.
-    modMask = mod4Mask
+    modMask = mod4Mask,
+    startupHook = composeAll [
+        startupHook gnomeConfig,
+        -- fix fullscreen for Firefox
+        -- https://gist.github.com/sboehler/5f48017a6b53805485180a9a6d81196b
+        setFullscreenSupported
+    ],
+    handleEventHook = composeAll [
+        handleEventHook gnomeConfig,
+        -- fix fullscreen
+        fullscreenEventHook
+    ]
 } `additionalKeys` [
     -- Workaround for
     -- https://bugs.launchpad.net/ubuntu/+source/xmonad/+bug/1813049
     ((mod4Mask .|. shiftMask, xK_q), spawn "gnome-session-quit --logout")
     ]
+
+setFullscreenSupported :: X ()
+setFullscreenSupported = withDisplay $ \dpy -> do
+    r <- asks theRoot
+    a <- getAtom "_NET_SUPPORTED"
+    c <- getAtom "ATOM"
+    supp <- mapM getAtom [
+        "_NET_WM_STATE_HIDDEN",
+        "_NET_WM_STATE_FULLSCREEN", -- XXX Copy-pasted to add this line
+        "_NET_NUMBER_OF_DESKTOPS",
+        "_NET_CLIENT_LIST",
+        "_NET_CLIENT_LIST_STACKING",
+        "_NET_CURRENT_DESKTOP",
+        "_NET_DESKTOP_NAMES",
+        "_NET_ACTIVE_WINDOW",
+        "_NET_WM_DESKTOP",
+        "_NET_WM_STRUT"
+        ]
+    io $ changeProperty32 dpy r a c propModeReplace (fmap fromIntegral supp)
+    setWMName "xmonad"