This was actually logged against what looks like an older repository at https://github.com/allanlw/hot-babe/issues/1. Using xorg, specifying geometry in either command line or config file has no apparent effect. gdk_window_get_geometry gets the position requested in the window creation, but this seems unrelated to the actual window position. I'm beginning to wonder if this is because this is a top level gdk window, not a gtk window. The positioning is relative to the parent window - but perhaps only if the parent is a gtkwindow? Before I go trying to add an extra layer of a gtk window, does this make sense to anyone else? Note: the window always goes to the top left of the current monitor, but will not overlay a previous instance, nor does it seem to overlay the top left corner of any other main window.