Search Background setting doesn’t appear to exist

I’m looking to simply change the background image of the Search (Like the city scene here: https://demo.directorist.com/theme/dlist/).

I’ve looked everywhere and I’m sure I’m simply missing it – I’ve done a search in the code base and it looks to me it should be under: Directory listings > Settings > Search

However it’s simply not there, the last setting I can see is: Display Popular Categories.

In the codebase (/wp-content/plugins/directorist/includes/classes/class-settings-panel.php) Display Popular Categories has a key of ‘show_popular_category’ and sits 2 places above ‘search_home_bg’ in the array.

So essentially I have no idea where to find this setting in the UI – It’s not where it appears (to me) that it should be so if someone could point me in the right direction that’d be fantastic.

Cheers