typo in custom identity provider docs (#1517)

Author: yrobag

src/pages/extending-chat-widget/custom-identity-provider/index.mdx

@@ -38,7 +38,7 @@ function () {
 </CodeSample>
 </Code>
 
-You can define it as a part of the [LiveChatWidget object](https://platform.text.com/docs/extending-chat-widget/javascript-api/#getting-started) from the tracking code used to install the Chat Widget on your website or from any other place with access to the `window._lc` object (in case of more advanced applications). However, **it has to be provided before widget initialization**.
+You can define it as a part of the [LiveChatWidget object](https://platform.text.com/docs/extending-chat-widget/javascript-api/#getting-started) from the tracking code used to install the Chat Widget on your website or from any other place with access to the `window.__lc` object (in case of more advanced applications). However, **it has to be provided before widget initialization**.
 
 <Code>
 <CodeSample path={'CUSTOM IDENTITY PROVIDER'}>