How to retrieve ChatterExtension using package.xml or manifest
Syntax to fetch ChatterExtension metadata
<?xml version="1.0" encoding="UTF-8"?>
<Package xmlns="http://soap.sforce.com/2006/04/metadata">
<types>
<name>ChatterExtension</name>
<members>*</members>
</types>
<version>62.0</version>
</Package>
