### Godot version

4.1 rc3

### System information

Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 (NVIDIA; 30.0.15.1403) - Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz (8 Threads)

### Issue description

This™
![image](https://github.com/godotengine/godot/assets/2223172/cb33110f-a5b0-400a-951f-3fa425f05714)

It can still happen, but it's more difficult to trigger.

### Steps to reproduce

1. Create a new scene with a Control node
2. Add Theme to the Control
3. Open Theme Editor
4. Clear the `theme` property in Control
5. Save, with Theme Editor opened
6. Restart

### Minimal reproduction project

N/A
if (bool(EDITOR_GET("run/output/always_clear_output_on_play"))) {
		log->clear();
	}
	if (bool(EDITOR_GET("run/output/always_open_output_on_play"))) {
		make_bottom_panel_item_visible(log);
	}
}
void EditorNode::_project_run_stopped() {
	if (!bool(EDITOR_GET("run/output/always_close_output_on_stop"))) {
		return;
	}
	for (int i = 0; i < bottom_panel_items.size(); i++) {
		if (bottom_panel_items[i].control == log) {
			_bottom_panel_switch(false, i);
			break;
		}
	}
}
void EditorNode::notify_all_debug_sessions_exited() {
	project_run_bar->stop_playing();
}
void EditorNode::add_io_error(const String &p_error) {
	DEV_ASSERT(Thread::get_caller_id() == Thread::get_main_id());
	singleton->load_errors->add_image(singleton->gui_base->get_theme_icon(SNAME("Error"), SNAME("EditorIcons")));
	singleton->load_errors->add_text(p_error + "\n");
	EditorInterface::get_singleton()->popup_dialog_centered_ratio(singleton->load_error_dialog, 0.5);
}
void EditorNode::add_io_warning(const String &p_warning) {