### Tested versions

Caused by [0d6300d269b818e6c3d3ea9cbc592480103aa6d0] Fix folder color not showing up in file dialogs
https://github.com/godotengine/godot/pull/84837
(git bisection)

### System information

Godot v4.3.dev (6faa5c6dc) - Fedora Linux 39 (Workstation Edition) - Wayland - Vulkan (Forward+) - dedicated AMD Radeon RX Vega (RADV VEGA10) () - AMD Ryzen 7 5800X 8-Core Processor (16 Threads)

### Issue description

When opening the export path, it results in a black popup.

![image](https://github.com/godotengine/godot/assets/270928/d67dee6a-f1e1-4bf3-8a3f-419554269f4a)


### Steps to reproduce

1. Open export settings
2. Add an export target
3. Try to select an export path

### Minimal reproduction project (MRP)

n/a
set_process(false);
	preview_waiting = false;
	if (p_preview.is_valid() && get_current_path() == p_path) {
		preview->set_texture(p_preview);
		if (display_mode == DISPLAY_THUMBNAILS) {
			preview_vb->hide();
		} else {
			preview_vb->show();
		}
	} else {
		preview_vb->hide();
		preview->set_texture(Ref<Texture2D>());
	}
}
void EditorFileDialog::_request_single_thumbnail(const String &p_path) {
	if (!FileAccess::exists(p_path) || !previews_enabled) {
		return;
	}
	set_process(true);
	preview_waiting = true;
	preview_wheel_timeout = 0;
	EditorResourcePreview::get_singleton()->queue_resource_preview(p_path, this, "_thumbnail_done", p_path);
}
void EditorFileDialog::_action_pressed() {