The help overlay should be an override-redirect (GTK_TYPE_POPUP) window. That will stop the full-screen logic from kicking in.

Agreed.

Created attachment 249485 [details] [review]
wacom: Make the OSD Window be a popup one

This is necessary because, otherwise, showing the OSD Window on top of
a fullscreen window will hide the latter.

I had to explicitly grab the keyboard or else the window wouldn't get the user input (necessary to hide it when pressing Escape).

Review of attachment 249485 [details] [review]:

How will this interact with other shortcuts, like Alt+Tab?

::: plugins/wacom/gsd-wacom-osd-window.c
@@ +1424,3 @@
+grab_keyboard (GsdWacomOSDWindow *self)
+{
+	GdkDevice *device, *keyb;

*kbd is better.

@@ +1428,3 @@
+
+	gdk_window = gtk_widget_get_window (GTK_WIDGET (self));
+	device = gtk_get_current_event_device ();

That's useless. If you clicked on the button to show the keyboard, this will be NULL.

@@ +1447,3 @@
+		keyb = device;
+	else
+		keyb = gdk_device_get_associated_device (device);

Run a for loop on the devices from gdk_device_manager_list_devices() and check their types instead.

@@ +1457,3 @@
+			     GDK_KEY_PRESS_MASK | GDK_KEY_RELEASE_MASK,
+			     NULL, GDK_CURRENT_TIME) != GDK_GRAB_SUCCESS) {
+		g_warning ("Could not grab the keyboard device...");

To print that sort of thing, I'm not sure that we need to know.

Created attachment 249810 [details] [review]
wacom: Make the OSD Window be a popup one

New version with Bastien's suggested changes.

Review of attachment 249810 [details] [review]:

Looks fine after that.

::: plugins/wacom/gsd-wacom-osd-window.c
@@ +1435,3 @@
+	devices = gdk_device_manager_list_devices (device_manager, GDK_DEVICE_TYPE_MASTER);
+
+	for (l = devices; l != NULL; l = g_list_next (l)) {

l = l->next

@@ +1446,3 @@
+	g_list_free (devices);
+
+	if (kbd == NULL) {

g_assert (kbd);
it's impossible for this to happen so an assertion is in order.

Review of attachment 249810 [details] [review]:

Looks fine after that.

::: plugins/wacom/gsd-wacom-osd-window.c
@@ +1435,3 @@
+	devices = gdk_device_manager_list_devices (device_manager, GDK_DEVICE_TYPE_MASTER);
+
+	for (l = devices; l != NULL; l = g_list_next (l)) {

l = l->next

@@ +1446,3 @@
+	g_list_free (devices);
+
+	if (kbd == NULL) {

g_assert (kbd);
it's impossible for this to happen so an assertion is in order.

Pushed.

commit ff4406ccf0cd83868320ce6cbc0ad8a8b47f1cee