adding versionadded

Author: weaverryan

src/LiveComponent/doc/index.rst

@@ -1987,6 +1987,10 @@ You can also trigger a specific "action" instead of a normal re-render:
 Communication Between Components: Emitting Events
 -------------------------------------------------
 
+.. versionadded:: 2.8
+
+    The ability to emit events was added in Live Components 2.8.
+
 Events allow you to communicate between any two components that live
 on your page.
 
@@ -2178,6 +2182,11 @@ Suppose the user updates the ``listName`` model and the parent component
 re-renders. In this case, the child component will *not* re-render by design:
 each component lives in its own universe.
 
+.. versionadded:: 2.8
+
+    The ``updateFromParent`` option was added in Live Components 2.8. Previously,
+    a child would re-render when *any* props passed into it changed.
+
 However, if the user adds a *new* todo item then we *do* want the ``todo_footer``
 child component to re-render: using the new ``count`` value. To trigger this,
 in the ``todo_footer`` component, add the ``updateFromParent`` option::