Comment 9 for bug 1718238

In the buggy case, xprop only reports one icon of size 48.

In the correct case, xprop reports 6 icons of sizes 22, 16, 48, 24, 32 and finally 48 again, all looking like taken from Humanity. (This isn't what I saw here a couple of days ago in the dup bugreport, I've no idea about the cause of this difference.)

Apart from these, the only differences in xprop's output are "bitmap id # to use for icon", "bitmap id # of mask for icon" and "_NET_WM_USER_TIME(CARDINAL)".

Just as the visible icon itself, xprop's output is also not updated immediately when installing/removing gnome-icon-theme, only on certain operatons such as opening a new gnome-terminal tab or window (including Find, Preferences, About windows), or opening its Terminal menu. This makes me still heavily suspect that the icon is indeed taken from the "_NET_WM_ICON(CARDINAL)" X property. But then how do the files shipped by gnome-icon-theme come into the game???

I've double checked that gnome-terminal only performs the "gtk_window_set_default_icon_name (GNOME_TERMINAL_ICON_NAME)" once at startup, so it's not this call setting the X properties directly, but probably GTK+ doing it sometimes under the hood.

This xprop thingy seems to be a dead end for investigation. We'd need to locate the exact piece of software displaying that icon (gnome-shell? mutter?) and start debugging that.