Product abandonment campaigns allow you to retarget window shoppers who browsed a product but didn’t add it to the cart or purchase it in messenger.
The percentage of visitors on your website falling into this category is huge, even higher than the number of people abandoning their carts.  

Go to auto-campaigns in the sidebar and select shopper from the customer journey stages. From here select product abandonment campaign.
Now in the editor you can edit the messages, change the images, change the timing, add a discount code and once you're done, click on save and turn on the campaign. 

Your users will see the products they viewed most recently. 

We use a standard 72-attribution period like Facebook Ads and email marketing platforms. This means that someone viewing or clicking on the message sent and purchasing within 72 hours would be attributed as a sale from BiteSpeed.

A visitor who has opted in to messenger using any of the opt-in tools and has browsed a product but not purchased it will receive the message.
If someone adds a product to the cart before the product abandonment campaign is delivered, they would be delivered the abandoned cart campaign instead.
If someone purchases the product before the campaign is sent, they will not receive the campaign.

After setting up the campaign, open up your store URL in an incognito window, opt-in to messenger using any of the opt-in tools on your website, browse a product and then close the tab. After the time period set for the product abandonment campaign to be delivered, you'll receive it in messenger.