Add note about nested properties

Author: ashton-huxtable

src/connections/destinations/catalog/facebook-pixel/index.md

@@ -239,5 +239,9 @@ If someone saw or clicked on your ad on a mobile phone then later came back dire
 
 Facebook Pixel events typically don't display in real-time within the Facebook Ads Manager or other reporting interfaces. While Facebook Pixel events are tracked in near real-time, there might be some delay before you see them in your reporting. Visit [Facebook's documentation](https://www.facebook.com/business/help/147965221941551){:target="_blank"} to learn more. 
 
+### Blocklisting nested properties 
+
+Segment does not handle nested properties that need to be blocklisted, including the standard PII properties. If you have standard PII properties or other properties you would like to blocklist, you can use [destination filters](https://segment.com/docs/connections/destinations/destination-filters/) to drop those properties before they are sent downstream. 
+
 
 {% include content/client-side-script-unverified.md %}