Comment 34 for bug 1491064

lacking any experience with GTK, I had a quick peek at the source and noticed that the text-tool calls sp_event_context_update_cursor in the input event processing quite a bit, whereas select-tool does not do that. Instead, select-tool calls gdk_window_set_cursor(window,...) in the GDK_ENTER_NOTIFY and GDK_LEAVE_NOTIFY events (which are not handled by text-tool at all).

Sorry if I am sending people on a goose-chase here. I just found this mouse-in-window dependency of the slow-down very curious!