Porto Theme problem: Uncaught SyntaxError, image not loading

20 hours ago support posted this…

  1. Please upload all required theme patches mentioned in theme package to your site directory (from Patch for Magento 2.2.x > patch for Magento 2.3.1 & above)

  2. You can see the changes of each theme version in Porto preview page https://themeforest.net/item/porto-ultimate-responsive-magento-theme/9725864

That sorted it!