Setting "Select Default Source" not working for Search in AGOL Web App

[BenVan_Kesteren1]

Hey, 

I have a web app setup, and there are two layers which I would like the users to be able to search, Water Main and Road Name.

At the bottom of the Search Options panel, there is an option to set 'select default search', which I assume means that whatever is set here, will be the default search option in the search window on my web app.

So I save this, and launch the page. But no matter how many times I have tried this, the Water Main search is ALWAYS the default option presented to me. I expect to see 'smith street' here, but instead I see AssetID:

I am wondering if:

1. Have I made an incorrect assumption? Is this not what this setting does?
2. Is this a bug in the matrix, and this happens to everyone?
3. Have I set this up incorrectly?

My full workflow is below as a GIF (click to enlarge), any assistance or pointers would be greatly appreciated.

Thanks for your time.