Q1. How does Intercart fire FB pixel?
Intercart implements exactly the same FB pixel firing logic as default Shopify checkout, please set FB Pixel ID to both Shopify and Intercart.
Q2. Will post-purchase revenue be posted back to FB?
Yes, enable this feature in Intercart FB Pixel advanced settings to post back post-purchase revenue to FB.
Q3. Will shipping cost value be posted back to FB?
Yes, enable this feature in Intercart FB Pixel advanced settings to post back shipping cost value to FB.
Q4. Which abandoned checkout apps are compatible?
Intercart synchorizes abandoned checkout data to Shopify, default Shopify abandoned checkouts email is not supported, any apps (email/SMS) that support Shopify Abandoned Checkouts are compatible, e.g. Klaviyo, Conversio, Abandonment Protector, etc.
More details, please refer to the article: How Intercart synchorizes abandoned checkouts to Shopify