The hs-scripts.com embed code, identified by the URL js.hs-scripts.com, is the entry-point for HubSpot embed codes and ensures that as you add new HubSpot features like messages or lead flows, these features are automatically added to your site for you.
Please note: if you're an existing HubSpot customer, you don't need to replace any existing embed codes to take advantage of this new entry-point; this is automatically handled for you.
The js.hs-scripts.com script doesn't do any website tracking or work itself; it simply loads on the other embed codes relevant to your HubSpot subscription on your website. Website features such as lead flows and messages are delivered in this way, in addition to the existing analytics tracking. Since each of these features are delivered by a different script, ad/privacy blockers can block just trackers (like track.hubspot.com and js.hs-analytics.net) without affecting website features (like lead flows and messages).