diff --git a/config/locales/server.en.yml b/config/locales/server.en.yml
index 5b11bcaa28b..5d8ba4ea395 100644
--- a/config/locales/server.en.yml
+++ b/config/locales/server.en.yml
@@ -5468,6 +5468,7 @@ en:
       comment_by: "Comment by"
       review_by: "Review by"
       pr_summary: "%{commits} commits changed %{changed_files} files with %{additions} additions and %{deletions} deletions"
+      no_description: "Contribute to %{repo} development by creating an account on GitHub."
 
   discourse_push_notifications:
     popup:
diff --git a/lib/onebox/engine/github_gist_onebox.rb b/lib/onebox/engine/github_gist_onebox.rb
index 5ddcb2bbc84..e79a9825bfe 100644
--- a/lib/onebox/engine/github_gist_onebox.rb
+++ b/lib/onebox/engine/github_gist_onebox.rb
@@ -16,6 +16,10 @@ module Onebox
         "https://api.github.com/gists/#{match[:sha]}"
       end
 
+      def self.priority
+        110 # overlaps with GithubRepoOnebox
+      end
+
       private
 
       def data
diff --git a/lib/onebox/engine/github_issue_onebox.rb b/lib/onebox/engine/github_issue_onebox.rb
index 5212208acc1..26eb731fba9 100644
--- a/lib/onebox/engine/github_issue_onebox.rb
+++ b/lib/onebox/engine/github_issue_onebox.rb
@@ -38,6 +38,7 @@ module Onebox
 
       def data
         result = raw(github_auth_header(match[:org])).clone
+        repo = load_repo
         created_at = Time.parse(result["created_at"])
         closed_at = Time.parse(result["closed_at"]) if result["closed_at"]
         body, excerpt = compute_body(result["body"])
@@ -65,8 +66,21 @@ module Onebox
           avatar: "https://avatars1.githubusercontent.com/u/#{result["user"]["id"]}?v=2&s=96",
           domain: "#{ulink.host}/#{ulink.path.split("/")[1]}/#{ulink.path.split("/")[2]}",
           i18n: i18n,
+          is_private: repo["private"],
         }
       end
+
+      private
+
+      def load_repo
+        load_json("https://api.github.com/repos/#{match[:org]}/#{match[:repo]}")
+      end
+
+      def load_json(url)
+        ::MultiJson.load(
+          URI.parse(url).open({ read_timeout: timeout }.merge(github_auth_header(match[:org]))),
+        )
+      end
     end
   end
 end
diff --git a/lib/onebox/engine/github_pull_request_onebox.rb b/lib/onebox/engine/github_pull_request_onebox.rb
index 91ba259cf16..3ddb048d52e 100644
--- a/lib/onebox/engine/github_pull_request_onebox.rb
+++ b/lib/onebox/engine/github_pull_request_onebox.rb
@@ -62,6 +62,7 @@ module Onebox
             deletions: result["deletions"],
           },
         )
+        result["is_private"] = result.dig("base", "repo", "private")
 
         result
       end
@@ -100,7 +101,9 @@ module Onebox
       end
 
       def load_json(url)
-        ::MultiJson.load(URI.parse(url).open(read_timeout: timeout))
+        ::MultiJson.load(
+          URI.parse(url).open({ read_timeout: timeout }.merge(github_auth_header(match[:org]))),
+        )
       end
     end
   end
diff --git a/lib/onebox/engine/github_repo_onebox.rb b/lib/onebox/engine/github_repo_onebox.rb
new file mode 100644
index 00000000000..bd785606378
--- /dev/null
+++ b/lib/onebox/engine/github_repo_onebox.rb
@@ -0,0 +1,57 @@
+# frozen_string_literal: true
+
+require_relative "../mixins/github_body"
+require_relative "../mixins/github_auth_header"
+
+module Onebox
+  module Engine
+    class GithubRepoOnebox
+      include Engine
+      include LayoutSupport
+      include JSON
+      include Onebox::Mixins::GithubAuthHeader
+
+      GITHUB_COMMENT_REGEX = /(<!--.*?-->\r\n)/
+
+      matches_regexp(%r{^https?:\/\/(?:www\.)?(?!gist\.)[^\/]*github\.com\/[^\/]+\/[^\/]+\/?$})
+      always_https
+
+      def url
+        "https://api.github.com/repos/#{match[:org]}/#{match[:repository]}"
+      end
+
+      private
+
+      def match
+        @match ||= @url.match(%r{github\.com/(?<org>[^/]+)/(?<repository>[^/]+)})
+      end
+
+      def data
+        result = raw(github_auth_header(match[:org])).clone
+        result["link"] = link
+        description = result["description"]
+        title = "GitHub - #{result["full_name"]}"
+
+        if description.blank?
+          description = I18n.t("onebox.github.no_description", repo: result["full_name"])
+        else
+          title += ": #{Onebox::Helpers.truncate(description)}"
+        end
+
+        result["description"] = description
+        result["title"] = title
+        result["is_private"] = result["private"]
+
+        # The SecureRandom part of this doesn't matter, it's just used for caching the
+        # repo thumbnail which is generated on the fly by GitHub. There isn't detail
+        # in https://github.blog/2021-06-22-framework-building-open-graph-images/,
+        # but this SO answer https://stackoverflow.com/a/69043743 suggests this is
+        # how it works and testing confirms it.
+        result[
+          "thumbnail"
+        ] = "https://opengraph.githubassets.com/#{SecureRandom.hex}/#{match[:org]}/#{match[:repository]}"
+        result
+      end
+    end
+  end
+end
diff --git a/lib/onebox/templates/githubissue.mustache b/lib/onebox/templates/githubissue.mustache
index c241e08cefe..05d542b2137 100644
--- a/lib/onebox/templates/githubissue.mustache
+++ b/lib/onebox/templates/githubissue.mustache
@@ -1,5 +1,5 @@
 <div class="github-row">
-  <div class="github-icon-container" title="Issue">
+  <div class="github-icon-container" title="Issue" data-github-private-repo="{{is_private}}">
 	  <svg width="60" height="60" class="github-icon" viewBox="0 0 14 16" version="1.1" aria-hidden="true"><path fill-rule="evenodd" d="M7 2.3c3.14 0 5.7 2.56 5.7 5.7s-2.56 5.7-5.7 5.7A5.71 5.71 0 0 1 1.3 8c0-3.14 2.56-5.7 5.7-5.7zM7 1C3.14 1 0 4.14 0 8s3.14 7 7 7 7-3.14 7-7-3.14-7-7-7zm1 3H6v5h2V4zm0 6H6v2h2v-2z"></path></svg>
   </div>
 
diff --git a/lib/onebox/templates/githubpullrequest.mustache b/lib/onebox/templates/githubpullrequest.mustache
index c57f08e8274..a87a90c5ec8 100644
--- a/lib/onebox/templates/githubpullrequest.mustache
+++ b/lib/onebox/templates/githubpullrequest.mustache
@@ -1,4 +1,4 @@
-<div class="github-row">
+<div class="github-row" data-github-private-repo="{{is_private}}">
   {{#commit}}
     <div class="github-icon-container" title="Commit">
       <svg width="60" height="60" class="github-icon" viewBox="0 0 16 16" version="1.1" aria-hidden="true"><path fill-rule="evenodd" d="M10.5 7.75a2.5 2.5 0 11-5 0 2.5 2.5 0 015 0zm1.43.75a4.002 4.002 0 01-7.86 0H.75a.75.75 0 110-1.5h3.32a4.001 4.001 0 017.86 0h3.32a.75.75 0 110 1.5h-3.32z"></path></svg>
diff --git a/lib/onebox/templates/githubrepo.mustache b/lib/onebox/templates/githubrepo.mustache
new file mode 100644
index 00000000000..a9469802f8f
--- /dev/null
+++ b/lib/onebox/templates/githubrepo.mustache
@@ -0,0 +1,9 @@
+<div class="github-row" data-github-private-repo="{{is_private}}">
+  <img width="695" height="347" src="{{thumbnail}}" class="thumbnail">
+
+  <h3><a href="{{link}}" target="_blank" rel="noopener ugc noopener">{{title}}</a></h3>
+
+  {{#description}}
+    <p><span class="github-repo-description">{{description}}</span></p>
+  {{/description}}
+</div>
diff --git a/spec/fixtures/onebox/githubrepo.response b/spec/fixtures/onebox/githubrepo.response
new file mode 100644
index 00000000000..c5189bf7298
--- /dev/null
+++ b/spec/fixtures/onebox/githubrepo.response
@@ -0,0 +1,146 @@
+{
+  "id": 7569578,
+  "node_id": "MDEwOlJlcG9zaXRvcnk3NTY5NTc4",
+  "name": "discourse",
+  "full_name": "discourse/discourse",
+  "private": false,
+  "owner": {
+    "login": "discourse",
+    "id": 3220138,
+    "node_id": "MDEyOk9yZ2FuaXphdGlvbjMyMjAxMzg=",
+    "avatar_url": "https://avatars.githubusercontent.com/u/3220138?v=4",
+    "gravatar_id": "",
+    "url": "https://api.github.com/users/discourse",
+    "html_url": "https://github.com/discourse",
+    "followers_url": "https://api.github.com/users/discourse/followers",
+    "following_url": "https://api.github.com/users/discourse/following{/other_user}",
+    "gists_url": "https://api.github.com/users/discourse/gists{/gist_id}",
+    "starred_url": "https://api.github.com/users/discourse/starred{/owner}{/repo}",
+    "subscriptions_url": "https://api.github.com/users/discourse/subscriptions",
+    "organizations_url": "https://api.github.com/users/discourse/orgs",
+    "repos_url": "https://api.github.com/users/discourse/repos",
+    "events_url": "https://api.github.com/users/discourse/events{/privacy}",
+    "received_events_url": "https://api.github.com/users/discourse/received_events",
+    "type": "Organization",
+    "site_admin": false
+  },
+  "html_url": "https://github.com/discourse/discourse",
+  "description": "A platform for community discussion. Free, open, simple.",
+  "fork": false,
+  "url": "https://api.github.com/repos/discourse/discourse",
+  "forks_url": "https://api.github.com/repos/discourse/discourse/forks",
+  "keys_url": "https://api.github.com/repos/discourse/discourse/keys{/key_id}",
+  "collaborators_url": "https://api.github.com/repos/discourse/discourse/collaborators{/collaborator}",
+  "teams_url": "https://api.github.com/repos/discourse/discourse/teams",
+  "hooks_url": "https://api.github.com/repos/discourse/discourse/hooks",
+  "issue_events_url": "https://api.github.com/repos/discourse/discourse/issues/events{/number}",
+  "events_url": "https://api.github.com/repos/discourse/discourse/events",
+  "assignees_url": "https://api.github.com/repos/discourse/discourse/assignees{/user}",
+  "branches_url": "https://api.github.com/repos/discourse/discourse/branches{/branch}",
+  "tags_url": "https://api.github.com/repos/discourse/discourse/tags",
+  "blobs_url": "https://api.github.com/repos/discourse/discourse/git/blobs{/sha}",
+  "git_tags_url": "https://api.github.com/repos/discourse/discourse/git/tags{/sha}",
+  "git_refs_url": "https://api.github.com/repos/discourse/discourse/git/refs{/sha}",
+  "trees_url": "https://api.github.com/repos/discourse/discourse/git/trees{/sha}",
+  "statuses_url": "https://api.github.com/repos/discourse/discourse/statuses/{sha}",
+  "languages_url": "https://api.github.com/repos/discourse/discourse/languages",
+  "stargazers_url": "https://api.github.com/repos/discourse/discourse/stargazers",
+  "contributors_url": "https://api.github.com/repos/discourse/discourse/contributors",
+  "subscribers_url": "https://api.github.com/repos/discourse/discourse/subscribers",
+  "subscription_url": "https://api.github.com/repos/discourse/discourse/subscription",
+  "commits_url": "https://api.github.com/repos/discourse/discourse/commits{/sha}",
+  "git_commits_url": "https://api.github.com/repos/discourse/discourse/git/commits{/sha}",
+  "comments_url": "https://api.github.com/repos/discourse/discourse/comments{/number}",
+  "issue_comment_url": "https://api.github.com/repos/discourse/discourse/issues/comments{/number}",
+  "contents_url": "https://api.github.com/repos/discourse/discourse/contents/{+path}",
+  "compare_url": "https://api.github.com/repos/discourse/discourse/compare/{base}...{head}",
+  "merges_url": "https://api.github.com/repos/discourse/discourse/merges",
+  "archive_url": "https://api.github.com/repos/discourse/discourse/{archive_format}{/ref}",
+  "downloads_url": "https://api.github.com/repos/discourse/discourse/downloads",
+  "issues_url": "https://api.github.com/repos/discourse/discourse/issues{/number}",
+  "pulls_url": "https://api.github.com/repos/discourse/discourse/pulls{/number}",
+  "milestones_url": "https://api.github.com/repos/discourse/discourse/milestones{/number}",
+  "notifications_url": "https://api.github.com/repos/discourse/discourse/notifications{?since,all,participating}",
+  "labels_url": "https://api.github.com/repos/discourse/discourse/labels{/name}",
+  "releases_url": "https://api.github.com/repos/discourse/discourse/releases{/id}",
+  "deployments_url": "https://api.github.com/repos/discourse/discourse/deployments",
+  "created_at": "2013-01-12T00:25:55Z",
+  "updated_at": "2024-07-17T05:24:55Z",
+  "pushed_at": "2024-07-17T06:18:53Z",
+  "git_url": "git://github.com/discourse/discourse.git",
+  "ssh_url": "git@github.com:discourse/discourse.git",
+  "clone_url": "https://github.com/discourse/discourse.git",
+  "svn_url": "https://github.com/discourse/discourse",
+  "homepage": "https://www.discourse.org",
+  "size": 654594,
+  "stargazers_count": 41215,
+  "watchers_count": 41215,
+  "language": "Ruby",
+  "has_issues": false,
+  "has_projects": false,
+  "has_downloads": true,
+  "has_wiki": false,
+  "has_pages": false,
+  "has_discussions": false,
+  "forks_count": 8210,
+  "mirror_url": null,
+  "archived": false,
+  "disabled": false,
+  "open_issues_count": 59,
+  "license": {
+    "key": "gpl-2.0",
+    "name": "GNU General Public License v2.0",
+    "spdx_id": "GPL-2.0",
+    "url": "https://api.github.com/licenses/gpl-2.0",
+    "node_id": "MDc6TGljZW5zZTg="
+  },
+  "allow_forking": true,
+  "is_template": false,
+  "web_commit_signoff_required": false,
+  "topics": [
+    "discourse",
+    "ember",
+    "forum",
+    "javascript",
+    "postgresql",
+    "rails",
+    "ruby"
+  ],
+  "visibility": "public",
+  "forks": 8210,
+  "open_issues": 59,
+  "watchers": 41215,
+  "default_branch": "main",
+  "permissions": {
+    "admin": false,
+    "maintain": true,
+    "push": true,
+    "triage": true,
+    "pull": true
+  },
+  "custom_properties": {
+
+  },
+  "organization": {
+    "login": "discourse",
+    "id": 3220138,
+    "node_id": "MDEyOk9yZ2FuaXphdGlvbjMyMjAxMzg=",
+    "avatar_url": "https://avatars.githubusercontent.com/u/3220138?v=4",
+    "gravatar_id": "",
+    "url": "https://api.github.com/users/discourse",
+    "html_url": "https://github.com/discourse",
+    "followers_url": "https://api.github.com/users/discourse/followers",
+    "following_url": "https://api.github.com/users/discourse/following{/other_user}",
+    "gists_url": "https://api.github.com/users/discourse/gists{/gist_id}",
+    "starred_url": "https://api.github.com/users/discourse/starred{/owner}{/repo}",
+    "subscriptions_url": "https://api.github.com/users/discourse/subscriptions",
+    "organizations_url": "https://api.github.com/users/discourse/orgs",
+    "repos_url": "https://api.github.com/users/discourse/repos",
+    "events_url": "https://api.github.com/users/discourse/events{/privacy}",
+    "received_events_url": "https://api.github.com/users/discourse/received_events",
+    "type": "Organization",
+    "site_admin": false
+  },
+  "network_count": 8210,
+  "subscribers_count": 901
+}
diff --git a/spec/lib/onebox/engine/github_issue_onebox_spec.rb b/spec/lib/onebox/engine/github_issue_onebox_spec.rb
index 298df414a20..1537564e6d9 100644
--- a/spec/lib/onebox/engine/github_issue_onebox_spec.rb
+++ b/spec/lib/onebox/engine/github_issue_onebox_spec.rb
@@ -2,12 +2,15 @@
 
 RSpec.describe Onebox::Engine::GithubIssueOnebox do
   let(:issue_uri) { "https://api.github.com/repos/discourse/discourse/issues/1" }
+  let(:repo_uri) { "https://api.github.com/repos/discourse/discourse" }
+  let(:repo_response) { onebox_response("githubrepo") }
 
   before do
     stub_request(:get, issue_uri).to_return(
       status: 200,
       body: onebox_response("github_issue_onebox"),
     )
+    stub_request(:get, repo_uri).to_return(status: 200, body: repo_response)
   end
 
   include_context "with engines" do
@@ -23,6 +26,22 @@ RSpec.describe Onebox::Engine::GithubIssueOnebox do
       expect(html).to include(sanitized_label)
     end
 
+    it "sets the data-github-private-repo attr to false" do
+      expect(html).to include("data-github-private-repo=\"false\"")
+    end
+
+    context "when the PR is in a private repo" do
+      let(:repo_response) do
+        resp = MultiJson.load(onebox_response("githubrepo"))
+        resp["private"] = true
+        MultiJson.dump(resp)
+      end
+
+      it "sets the data-github-private-repo attr to true" do
+        expect(html).to include("data-github-private-repo=\"true\"")
+      end
+    end
+
     context "when github_onebox_access_token is configured" do
       before { SiteSetting.github_onebox_access_tokens = "discourse|github_pat_1234" }
 
diff --git a/spec/lib/onebox/engine/github_pull_request_onebox_spec.rb b/spec/lib/onebox/engine/github_pull_request_onebox_spec.rb
index 7d366a677c8..3d983388e28 100644
--- a/spec/lib/onebox/engine/github_pull_request_onebox_spec.rb
+++ b/spec/lib/onebox/engine/github_pull_request_onebox_spec.rb
@@ -3,13 +3,9 @@
 RSpec.describe Onebox::Engine::GithubPullRequestOnebox do
   let(:gh_link) { "https://github.com/discourse/discourse/pull/1253/" }
   let(:api_uri) { "https://api.github.com/repos/discourse/discourse/pulls/1253" }
+  let(:response) { onebox_response(described_class.onebox_name) }
 
-  before do
-    stub_request(:get, api_uri).to_return(
-      status: 200,
-      body: onebox_response(described_class.onebox_name),
-    )
-  end
+  before { stub_request(:get, api_uri).to_return(status: 200, body: response) }
 
   include_context "with engines" do
     let(:link) { gh_link }
@@ -53,18 +49,37 @@ RSpec.describe Onebox::Engine::GithubPullRequestOnebox do
       expect(html).to include("http://meta.discourse.org/t/audio-html5-tag/8168")
       expect(html).not_to include("test comment")
     end
+
+    it "sets the data-github-private-repo attr to false" do
+      expect(html).to include("data-github-private-repo=\"false\"")
+    end
+
+    context "when the PR is in a private repo" do
+      let(:response) do
+        resp = MultiJson.load(onebox_response(described_class.onebox_name))
+        resp["base"]["repo"]["private"] = true
+        MultiJson.dump(resp)
+      end
+
+      it "sets the data-github-private-repo attr to true" do
+        expect(html).to include("data-github-private-repo=\"true\"")
+      end
+    end
   end
 
   context "with commit links" do
     let(:gh_link) do
       "https://github.com/discourse/discourse/pull/1253/commits/d7d3be1130c665cc7fab9f05dbf32335229137a6"
     end
+    let(:pr_commit_url) do
+      "https://api.github.com/repos/discourse/discourse/commits/d7d3be1130c665cc7fab9f05dbf32335229137a6"
+    end
 
     before do
-      stub_request(
-        :get,
-        "https://api.github.com/repos/discourse/discourse/commits/d7d3be1130c665cc7fab9f05dbf32335229137a6",
-      ).to_return(status: 200, body: onebox_response(described_class.onebox_name + "_commit"))
+      stub_request(:get, pr_commit_url).to_return(
+        status: 200,
+        body: onebox_response(described_class.onebox_name + "_commit"),
+      )
     end
 
     it "includes commit name" do
@@ -74,21 +89,50 @@ RSpec.describe Onebox::Engine::GithubPullRequestOnebox do
         "http://meta.discourse.org/t/audio-html5-tag/8168",
       )
     end
+
+    context "when github_onebox_access_token is configured" do
+      before { SiteSetting.github_onebox_access_tokens = "discourse|github_pat_1234" }
+
+      it "sends it as part of the request" do
+        html
+        expect(WebMock).to have_requested(:get, pr_commit_url).with(
+          headers: {
+            "Authorization" => "Bearer github_pat_1234",
+          },
+        )
+      end
+    end
   end
 
   context "with comment links" do
     let(:gh_link) { "https://github.com/discourse/discourse/pull/1253/#issuecomment-21597425" }
+    let(:comment_api_url) do
+      "https://api.github.com/repos/discourse/discourse/issues/comments/21597425"
+    end
 
     before do
-      stub_request(
-        :get,
-        "https://api.github.com/repos/discourse/discourse/issues/comments/21597425",
-      ).to_return(status: 200, body: onebox_response(described_class.onebox_name + "_comment"))
+      stub_request(:get, comment_api_url).to_return(
+        status: 200,
+        body: onebox_response(described_class.onebox_name + "_comment"),
+      )
     end
 
     it "includes comment" do
       expect(html).to include("You&#39;ve signed the CLA")
     end
+
+    context "when github_onebox_access_token is configured" do
+      before { SiteSetting.github_onebox_access_tokens = "discourse|github_pat_1234" }
+
+      it "sends it as part of the request" do
+        html
+        expect(WebMock).to have_requested(:get, api_uri).with(
+          headers: {
+            "Authorization" => "Bearer github_pat_1234",
+          },
+        )
+      end
+    end
   end
 
   context "when github_onebox_access_token is configured" do
diff --git a/spec/lib/onebox/engine/github_repo_onebox_spec.rb b/spec/lib/onebox/engine/github_repo_onebox_spec.rb
new file mode 100644
index 00000000000..6476a261451
--- /dev/null
+++ b/spec/lib/onebox/engine/github_repo_onebox_spec.rb
@@ -0,0 +1,72 @@
+# frozen_string_literal: true
+
+RSpec.describe Onebox::Engine::GithubRepoOnebox do
+  let(:gh_link) { "https://github.com/discourse/discourse" }
+  let(:api_uri) { "https://api.github.com/repos/discourse/discourse" }
+  let(:response) { onebox_response(described_class.onebox_name) }
+
+  before { stub_request(:get, api_uri).to_return(status: 200, body: response) }
+
+  include_context "with engines" do
+    let(:link) { gh_link }
+  end
+  it_behaves_like "an engine"
+
+  describe "#to_html" do
+    it "includes the description of the repo" do
+      expect(html).to include("A platform for community discussion. Free, open, simple.")
+    end
+
+    it "includes the name of the repo and truncated description for the title" do
+      expect(html).to include(
+        "GitHub - discourse/discourse: A platform for community discussion. Free, open,...",
+      )
+    end
+
+    it "includes a thumbnail url" do
+      SecureRandom.stubs(:hex).returns("1234")
+      expect(html).to include("https://opengraph.githubassets.com/1234/discourse/discourse")
+    end
+
+    it "sets the data-github-private-repo attr to false" do
+      expect(html).to include("data-github-private-repo=\"false\"")
+    end
+
+    context "when the PR is in a private repo" do
+      let(:response) do
+        resp = MultiJson.load(onebox_response(described_class.onebox_name))
+        resp["private"] = true
+        MultiJson.dump(resp)
+      end
+
+      it "sets the data-github-private-repo attr to true" do
+        expect(html).to include("data-github-private-repo=\"true\"")
+      end
+    end
+
+    context "when the repo has no description" do
+      let(:response) do
+        resp = onebox_response(described_class.onebox_name)
+        resp["description"] = ""
+        resp
+      end
+
+      it "includes a message about contributing to the repo" do
+        expect(html).to include(I18n.t("onebox.github.no_description", repo: "discourse/discourse"))
+      end
+    end
+  end
+
+  context "when github_onebox_access_token is configured" do
+    before { SiteSetting.github_onebox_access_tokens = "discourse|github_pat_1234" }
+
+    it "sends it as part of the request" do
+      html
+      expect(WebMock).to have_requested(:get, api_uri).with(
+        headers: {
+          "Authorization" => "Bearer github_pat_1234",
+        },
+      )
+    end
+  end
+end