Add preview widget documentation

deploy/preview-deployments.mdx

@@ -8,13 +8,13 @@
   Preview deployments are available on [Pro and Custom plans](https://mintlify.com/pricing?ref=preview-deployments).
 </Info>
 
 Preview deployments let you see how changes to your docs will look before merging to production. Each preview creates a shareable URL that updates automatically as you push new changes. 
 
 Preview URLs are publicly viewable by default. Share a preview link with anyone who needs to review your changes.
 
 ## Create preview deployments
 
 Preview deployments are created automatically through pull requests or manually from your dashboard.
 
 ### Automatic previews
 
@@ -51,12 +51,30 @@
   <img src="/images/previews/redeploy-preview-dark.png" alt="The Previews menu with the deploy button emphasized by an orange rectangle." className="hidden dark:block" />
 </Frame>
 
+## Preview widget
+
+The preview widget appears on preview deployments to help you quickly navigate and review changed files. It displays as a floating button in the bottom-right corner of your preview deployment.
+
+<Frame>
+  <img src="https://github.com/user-attachments/assets/599ef515-8446-4d25-906a-dece96c5dd0a" alt="Preview widget showing list of changed files" />
+</Frame>
+
+### Features
+
+- **Changed files list**: View all files that were added, modified, or removed in the preview deployment
+- **File status badges**: Each file displays a badge indicating whether it was added, modified, or removed
+- **Search**: Filter the changed files list by file path or page title
+- **Quick navigation**: Click any file to navigate directly to that page in the preview
+- **Drag-and-drop positioning**: Drag the widget to reposition it on the left or right side of the screen
+
+The preview widget only appears on preview deployments, not on your production site.
+
 ## Restrict access to preview deployments
 
 By default, preview deployments are publicly accessible to anyone with the URL. You can restrict access to authenticated members of your Mintlify organization.
 
 1. Navigate to the **Previews** section in the [Add-ons](https://dashboard.mintlify.com/products/addons) page of your dashboard.
 2. Click the **Preview authentication** toggle to enable or disable preview authentication.
   <Frame>
     <img src="/images/previews/preview-auth-light.png" alt="The preview authentication toggle in the Add-ons page" className="block dark:hidden" />
     <img src="/images/previews/preview-auth-dark.png" alt="The preview authentication toggle in the Add-ons page" className="hidden dark:block" />