What Does Subscribers On A Product Do?

We are on CS-Cart Multi Vendor and have hundreds of vendors. Many have asked what the Subscribers tab does on the product. I'm having a hard time figuring it out.

At first, I tried getting rid of it the tab by uninstalling the Newsletter Addon and Email Marketing Addon, but even with those addons uninstalled the Subscribers tab still exists on Product for our vendors.

Does anybody know how the Subscribers tab on Products works? How would a vendor selling in our marketplace leverage this function on their products?

I've attached an image of the tab I'm referring to.

Thanks for anyone who knows what this does.

Capture.PNG

It is a part of the out of stock actions and not related with newsletters

https://docs.cs-cart.com/latest/user_guide/manage_products/products/out_of_stock_actions.html