Initial focus is not reflected visually in emacs

[davidben]

Initial focus is not reflected visually in emacs

[davidben]

It's conceivable this is another (!) emacs bug? At least, urxvt does not show the same problem.

[davidben]

This is an emacs bug. In Fx_create_frame, the new window is only cons'd onto Vframe_list after a few calls, but the window is attached on x_window. In between, there are a number of calls to UNBLOCK_INPUT which pump the event loop. If the XEMBED_FOCUS_IN message comes in too early (before the frame is made official), x_detect_focus_change ignores the message and we get the visual artifact.

[davidben]

More findings: the reason emacs doesn't normally have problems here is because the window is mapped after it is added to Vframe_list. This means the Focusin events won't come in until emacs is ready. But GtkSocket sends XEMBED_FOCUS_IN immediately after sending XEMBED_EMBEDDED_NOTIFY instead of waiting for the window to be mapped. This seems clearly bogus, although I think the spec is pretty vague here. Probably worth a patch to GTK3, but that's not going to help this project any.

Probably worth trying to hack around this in emacs somehow or reimplementing XEmbed in the plugin, or at least messing with the GTK version.