### Godot version

v4.2.dev.custom_build [c3b0a92c3]

### System information

Debian Linux X11 Xfce

### Issue description

In the following scene tree it is not possible to write anything in `LineEditB`.
![image](https://github.com/godotengine/godot/assets/6299227/ce5f696a-d86a-402f-98f7-6a762f15543e)

I would expect, that it is possible to focus `LineEditB` with a mouse click and write into it.

Regression from #58334

### Steps to reproduce

1. Load and run MRP
2. Mouse Click into the left LineEditB
3. Type Keyboard => No letters appear in the LineEditB

Variant:

1. Load and run MRP
2. Mouse Click into the right LineEditA
3. Mouse Click into the left LineEditB
4. Type Keyboard => Letters appear in LineEditA instead of LineEditB


### Minimal reproduction project

[BugKeyInputRouting.zip](https://github.com/godotengine/godot/files/11994804/BugKeyInputRouting.zip)

ERR_READ_THREAD_GUARD_V(nullptr);
	return camera_3d;
}
void Viewport::_camera_3d_transform_changed_notify() {
}
void Viewport::_camera_3d_set(Camera3D *p_camera) {
	if (camera_3d == p_camera) {
		return;
	}
	if (camera_3d) {
		camera_3d->notification(Camera3D::NOTIFICATION_LOST_CURRENT);
	}
	camera_3d = p_camera;
	if (!camera_3d_override) {
		if (camera_3d) {
			RenderingServer::get_singleton()->viewport_attach_camera(viewport, camera_3d->get_camera());
		} else {
			RenderingServer::get_singleton()->viewport_attach_camera(viewport, RID());
		}
	}
	if (camera_3d) {
		camera_3d->notification(Camera3D::NOTIFICATION_BECAME_CURRENT);
	}
	_update_audio_listener_3d();
	_camera_3d_transform_changed_notify();
}
bool Viewport::_camera_3d_add(Camera3D *p_camera) {