how can I handle the character palette hotkey in an LSUIElement application

Question

I've implemented something like Cocoa Keyboard Shortcuts in Dialog without an Edit Menu for an LSUIElement application. In fact, to try to make sure I was not missing some obscure standard keybinding that I might forget to include, I just grabbed a standard "edit" menu and loaded it out of a nib file and then used my NSApplication subclass's sendEvent: to invoke its performKeyEquivalent: . This works as I expect.

However, the character palette (or "emoji picker", or "Emoji & Symbols") is not explicitly in this menu, so when I hit the hotkey (⌘⌃Space) nothing happens. Examining the objects, this is what I expect. However, when I hit this hotkey in a normal application, I see the Edit menu flash as if that's where the key's defined, even if it isn't. Stranger still, 🌐 still works even though the control-command-space one doesn't.

Where is this keyboard shortcut supposed to be handled? I don't want to do anything particularly custom here, I'd just like to correctly set up the default text-editing behavior that other apps get.