Documentation: PostPreviewButton editor component

packages/editor/README.md

@@ -1117,7 +1117,20 @@ Undocumented declaration.
 
 ### PostPreviewButton
 
-Undocumented declaration.
+Renders a button that opens a new window or tab for the preview, writes the interstitial message to this window, and then navigates to the actual preview link. The button is not rendered if the post is not viewable and disabled if the post is not saveable.
+
+_Parameters_
+
+-   _props_ `Object`: The component props.
+-   _props.className_ `string`: The class name for the button.
+-   _props.textContent_ `string`: The text content for the button.
+-   _props.forceIsAutosaveable_ `boolean`: Whether to force autosave.
+-   _props.role_ `string`: The role attribute for the button.
+-   _props.onPreview_ `Function`: The callback function for preview event.
+
+_Returns_
+
+-   `JSX.Element|null`: The rendered button component.
 
 ### PostPublishButton
 

packages/editor/src/components/post-preview-button/index.js

@@ -99,6 +99,21 @@ function writeInterstitialMessage( targetDocument ) {
 	targetDocument.close();
 }
 
+/**
+ * Renders a button that opens a new window or tab for the preview,
+ * writes the interstitial message to this window, and then navigates
+ * to the actual preview link. The button is not rendered if the post
+ * is not viewable and disabled if the post is not saveable.
+ *
+ * @param {Object}   props                     The component props.
+ * @param {string}   props.className           The class name for the button.
+ * @param {string}   props.textContent         The text content for the button.
+ * @param {boolean}  props.forceIsAutosaveable Whether to force autosave.
+ * @param {string}   props.role                The role attribute for the button.
+ * @param {Function} props.onPreview           The callback function for preview event.
+ *
+ * @return {JSX.Element|null} The rendered button component.
+ */
 export default function PostPreviewButton( {
 	className,
 	textContent,