Fix initial value assignment in BlockBindingConnector

Author: michalczaplinski

packages/block-editor/src/components/block-binding-support/with-block-binding-support.js

@@ -34,9 +34,9 @@ const BlockBindingConnector = ( {
 	blockProps,
 	args,
 } ) => {
-	const lastPropValue = useRef();
-	const lastAttrValue = useRef();
 	const { value, updateValue } = useSource( blockProps, args );
+	const lastPropValue = useRef( value );
+	const lastAttrValue = useRef( attrValue );
 
 	const setAttributes = blockProps.setAttributes;
 
@@ -49,6 +49,13 @@ const BlockBindingConnector = ( {
 		[ attrName, setAttributes ]
 	);
 
+	/* Set the initial value of the block attribute */
+	useEffect( () => {
+		setAttributes( {
+			[ attrName ]: value,
+		} );
+	}, [] );
+
 	/*
 	 * Source Prop => Block Attribute
 	 *