[MERGE 8/11 @ 8:45am PT] Codespaces Megabranch (#20378)

Adding Codespaces docs

content/github/collaborating-with-pull-requests/index.md

@@ -22,6 +22,6 @@ children:
   - /addressing-merge-conflicts
   - /reviewing-changes-in-pull-requests
   - /incorporating-changes-from-a-pull-request
-shortTitle: Collaborate with PRs
+shortTitle: Collaborate with pull requests
 ---
 

content/github/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/about-pull-requests.md

@@ -23,6 +23,8 @@ topics:
 
 {% endnote %}
 
+You can create pull requests on {% data variables.product.prodname_dotcom_the_website %}, with {% data variables.product.prodname_desktop %}, in {% data variables.product.prodname_codespaces %}, on {% data variables.product.prodname_mobile %}, and when using GitHub CLI.
+
 After initializing a pull request, you'll see a review page that shows a high-level overview of the changes between your branch (the compare branch) and the repository's base branch. You can add a summary of the proposed changes, review the changes made by commits, add labels, milestones, and assignees, and @mention individual contributors or teams. For more information, see "[Creating a pull request](/articles/creating-a-pull-request)."
 
 Once you've created a pull request, you can push commits from your topic branch to add them to your existing pull request. These commits will appear in chronological order within your pull request and the changes will be visible in the "Files changed" tab.

content/github/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request.md

@@ -151,6 +151,21 @@ gh pr create --web
 
 {% enddesktop %}
 
+{% ifversion fpt %}
+
+{% codespaces %}
+
+1. Once you've committed changes to your local copy of the repository, click the **Create Pull Request** icon. 
+![Source control side bar with staging button highlighted](/assets/images/help/codespaces/codespaces-commit-pr-button.png)  
+1. Check that the local branch and repository you're merging from, and the remote branch and repository you're merging into, are correct. Then give the pull request a title and a description. 
+![Source control side bar with staging button highlighted](/assets/images/help/codespaces/codespaces-commit-pr.png)
+1. Click **Create**.
+
+For more information on creating pull requests in {% data variables.product.prodname_codespaces %}, see "[Using Codespaces for pull requests](/codespaces/developing-in-codespaces/using-codespaces-for-pull-requests)."
+
+{% endcodespaces %}
+
+{% endif %}
 ## Further reading
 
 - "[Creating a pull request from a fork](/articles/creating-a-pull-request-from-a-fork)"

content/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/reviewing-proposed-changes-in-a-pull-request.md

@@ -21,6 +21,10 @@ You can review changes in a pull request one file at a time. While reviewing the
 
 ## Starting a review
 
+{% include tool-switcher %}
+
+{% webui %}
+
 {% data reusables.repositories.sidebar-pr %}
 {% data reusables.repositories.choose-pr-review %}
 {% data reusables.repositories.changed-files %}
@@ -33,8 +37,21 @@ You can review changes in a pull request one file at a time. While reviewing the
 Before you submit your review, your line comments are _pending_ and only visible to you. You can edit pending comments anytime before you submit your review. To cancel a pending review, including all of its pending comments, scroll down to the end of the timeline on the Conversation tab, then click **Cancel review**.
 
 ![Cancel review button](/assets/images/help/pull_requests/cancel-review-button.png)
+{% endwebui %}
 
 {% ifversion fpt %}
+
+{% codespaces %}
+
+You can use [{% data variables.product.prodname_codespaces %}](/codespaces/overview) to test, run, and review pull requests.
+
+{% data reusables.codespaces.review-pr %} 
+
+For more information on reviewing pull requests in {% data variables.product.prodname_codespaces %}, see "[Using Codespaces for pull requests](/codespaces/developing-in-codespaces/using-codespaces-for-pull-requests)."
+
+{% endcodespaces %}
+
+
 ## Reviewing dependency changes
 
 If the pull request contains changes to dependencies you can use the dependency review for a manifest or lock file to see what has changed and check whether the changes introduce security vulnerabilities. For more information, see "[Reviewing dependency changes in a pull request](/github/collaborating-with-issues-and-pull-requests/reviewing-dependency-changes-in-a-pull-request)."