Updated master -> main references (#3769)

content/docs/higher-order-components.md

@@ -297,7 +297,7 @@ The `compose` utility function is provided by many third-party libraries includi
 
 ## Convention: Wrap the Display Name for Easy Debugging {#convention-wrap-the-display-name-for-easy-debugging}
 
-The container components created by HOCs show up in the [React Developer Tools](https://github.com/facebook/react/tree/master/packages/react-devtools) like any other component. To ease debugging, choose a display name that communicates that it's the result of a HOC.
+The container components created by HOCs show up in the [React Developer Tools](https://github.com/facebook/react/tree/main/packages/react-devtools) like any other component. To ease debugging, choose a display name that communicates that it's the result of a HOC.
 
 The most common technique is to wrap the display name of the wrapped component. So if your higher-order component is named `withSubscription`, and the wrapped component's display name is `CommentList`, use the display name `WithSubscription(CommentList)`:
 

src/components/MarkdownPage/MarkdownPage.js

@@ -132,7 +132,7 @@ const MarkdownPage = ({
                     </span>
                     <a
                       css={sharedStyles.articleLayout.editLink}
-                      href={`https://github.com/reactjs/reactjs.org/tree/master/${markdownRemark.fields.path}`}>
+                      href={`https://github.com/reactjs/reactjs.org/tree/main/${markdownRemark.fields.path}`}>
                       Edit this page
                     </a>
                   </div>