### Godot version

v4.0.beta.custom_build [13f0158]

### System information

Windows 10

### Issue description

When doing operations (`begin_complex_operation` and `end_complex_operation`) with multiple selections in TextEdit, some of these selections don't revert upon undo. This behavior is affects some of script editor's operations, like duplicate selection and delete lines.

### Steps to reproduce

Open script editor, make multiple selections. Keep in mind what you have selected. Do duplicate selection (ctrl+shift+D). Undo (ctrl+Z). Compare the result to what you remember.

### Minimal reproduction project

N/A
}
			return false;
		}
		if (k->is_alt_pressed()) {
			if (!alt_start) {
				if (k->get_keycode() == Key::KP_ADD) {
					alt_start = true;
					alt_code = 0;
					return true;
				}
			} else {
				if (k->get_keycode() >= Key::KEY_0 && k->get_keycode() <= Key::KEY_9) {
					alt_code = alt_code << 4;
					alt_code += (uint32_t)(k->get_keycode() - Key::KEY_0);
				}
				if (k->get_keycode() >= Key::KP_0 && k->get_keycode() <= Key::KP_9) {
					alt_code = alt_code << 4;
					alt_code += (uint32_t)(k->get_keycode() - Key::KP_0);
				}
				if (k->get_keycode() >= Key::A && k->get_keycode() <= Key::F) {
					alt_code = alt_code << 4;
					alt_code += (uint32_t)(k->get_keycode() - Key::A) + 10;
				}
				return true;
			}
		}
	}
	return false;
}
void TextEdit::gui_input(const Ref<InputEvent> &p_gui_input) {