Merge branch 'v4-dev' of https://github.com/twbs/bootstrap into v4-dev

13 files changed, 38 insertions, 70 deletions

diff --git a/_config.yml b/_config.yml
index 3bc514e29..9ddbe2dff 100644
--- a/_config.yml
+++ b/_config.yml
@@ -15,7 +15,7 @@ port:             9001
 baseurl:          ""
 url:              https://getbootstrap.com
 encoding:         UTF-8
-exclude:          [.git, .github, assets/scss/, build, js, node_modules, nuget, scss, vendor, bower.json, composer.json, Gemfile, Gemfile.lock, Gruntfile.js, package.js, package.json, sache.json]
+exclude:          [.git, .github, assets/scss/, build, js, node_modules, nuget, scss, vendor, bower.json, composer.json, Gemfile, Gemfile.lock, Gruntfile.js, package.js, package.json, package-lock.json, sache.json]
 
 gems:
   - jekyll-redirect-from
diff --git a/_data/browser-features.yml b/_data/browser-features.yml
index c61eb4030..f19a460e6 100644
--- a/_data/browser-features.yml
+++ b/_data/browser-features.yml
@@ -7,7 +7,7 @@
     A11yUserVoice#16717318
   origin: >
     Bootstrap#20732
-    
+
 -
   browser: >
     Edge
diff --git a/_includes/docs-navbar.html b/_includes/docs-navbar.html
index 7d0cd281d..8d62d4585 100644
--- a/_includes/docs-navbar.html
+++ b/_includes/docs-navbar.html
@@ -15,16 +15,16 @@
         <a class="nav-link {% if page.title == "Examples" %}active{% endif %}" href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Examples');">Examples</a>
       </li>
       <li class="nav-item">
-        <a class="nav-link" href="{{ site.themes }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Themes');" target="_blank">Themes</a>
+        <a class="nav-link" href="{{ site.themes }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Themes');" target="_blank" rel="noopener">Themes</a>
       </li>
       <li class="nav-item">
-        <a class="nav-link" href="{{ site.jobs }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Jobs');" target="_blank">Jobs</a>
+        <a class="nav-link" href="{{ site.jobs }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Jobs');" target="_blank" rel="noopener">Jobs</a>
       </li>
       <li class="nav-item">
-        <a class="nav-link" href="{{ site.expo }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Expo');" target="_blank">Expo</a>
+        <a class="nav-link" href="{{ site.expo }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Expo');" target="_blank" rel="noopener">Expo</a>
       </li>
       <li class="nav-item">
-        <a class="nav-link" href="{{ site.blog }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Blog');" target="_blank">Blog</a>
+        <a class="nav-link" href="{{ site.blog }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Blog');" target="_blank" rel="noopener">Blog</a>
       </li>
     </ul>
   </div>
@@ -43,17 +43,17 @@
     </li>
 
     <li class="nav-item">
-      <a class="nav-link p-2" href="{{ site.repo }}" target="_blank" aria-label="GitHub">
+      <a class="nav-link p-2" href="{{ site.repo }}" target="_blank" rel="noopener" aria-label="GitHub">
         {% include icons/github.svg class="navbar-nav-svg" %}
       </a>
     </li>
     <li class="nav-item">
-      <a class="nav-link p-2" href="https://twitter.com/{{ site.twitter }}" target="_blank" aria-label="Twitter">
+      <a class="nav-link p-2" href="https://twitter.com/{{ site.twitter }}" target="_blank" rel="noopener" aria-label="Twitter">
         {% include icons/twitter.svg class="navbar-nav-svg" %}
       </a>
     </li>
     <li class="nav-item">
-      <a class="nav-link p-2" href="{{ site.slack }}" target="_blank" aria-label="Slack">
+      <a class="nav-link p-2" href="{{ site.slack }}" target="_blank" rel="noopener" aria-label="Slack">
         {% include icons/slack.svg class="navbar-nav-svg" %}
       </a>
     </li>
diff --git a/_includes/footer.html b/_includes/footer.html
index 19b05996f..968d42954 100644
--- a/_includes/footer.html
+++ b/_includes/footer.html
@@ -6,7 +6,7 @@
       <li><a href="{{ site.baseurl }}/examples/">Examples</a></li>
       <li><a href="{{ site.baseurl }}/about/history/">About</a></li>
     </ul>
-    <p>Designed and built with all the love in the world by <a href="https://twitter.com/mdo" target="_blank">@mdo</a> and <a href="https://twitter.com/fat" target="_blank">@fat</a>. Maintained by the <a href="https://github.com/orgs/twbs/people">core team</a> with the help of <a href="https://github.com/twbs/bootstrap/graphs/contributors">our contributors</a>.</p>
-    <p>Currently v{{ site.current_version }}. Code licensed <a rel="license" href="https://github.com/twbs/bootstrap/blob/master/LICENSE" target="_blank">MIT</a>, docs <a rel="license" href="https://creativecommons.org/licenses/by/3.0/" target="_blank">CC BY 3.0</a>.</p>
+    <p>Designed and built with all the love in the world by <a href="https://twitter.com/mdo" target="_blank" rel="noopener">@mdo</a> and <a href="https://twitter.com/fat" target="_blank" rel="noopener">@fat</a>. Maintained by the <a href="https://github.com/orgs/twbs/people">core team</a> with the help of <a href="https://github.com/twbs/bootstrap/graphs/contributors">our contributors</a>.</p>
+    <p>Currently v{{ site.current_version }}. Code licensed <a rel="license noopener" href="https://github.com/twbs/bootstrap/blob/master/LICENSE" target="_blank">MIT</a>, docs <a rel="license noopener" href="https://creativecommons.org/licenses/by/3.0/" target="_blank">CC BY 3.0</a>.</p>
   </div>
 </footer>
diff --git a/_includes/social.html b/_includes/social.html
index c488ea610..35bd9fde3 100644
--- a/_includes/social.html
+++ b/_includes/social.html
@@ -19,12 +19,17 @@
   <meta property="og:url" content="{{ site.url }}{{ page.url }}">
   <meta property="og:title" content="{{ page.title }}">
   <meta property="og:description" content="{{ page.description }}">
+  <meta property="og:type" content="website">
 {% else %}
   <meta property="og:url" content="{{ site.url }}">
   <meta property="og:title" content="{{ site.title }}">
   <meta property="og:description" content="{{ site.description }}">
 {% endif %}
-<meta property="og:image" content="{{ site.url }}{{ site.social_image_path }}">
+<meta property="og:image" content="{{ site.url | replace: 'https://', 'http://' }}{{ site.social_image_path }}">
+<meta property="og:image:secure_url" content="{{ site.url }}{{ site.social_image_path }}">
+<meta property="og:image:type" content="image/png">
+<meta property="og:image:width" content="1200">
+<meta property="og:image:height" content="630">
 
 <!-- Meta -->
 <meta name="description" content="{{ site.description }}">
diff --git a/assets/brand/bootstrap-outline.svg b/assets/brand/bootstrap-outline.svg
index 9f9794c23..8af913436 100644
--- a/assets/brand/bootstrap-outline.svg
+++ b/assets/brand/bootstrap-outline.svg
@@ -1,20 +1,6 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- Generator: Adobe Illustrator 17.1.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
-<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
-<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
-	 viewBox="0 180 612 612" enable-background="new 0 180 612 612" xml:space="preserve">
-<g id="outline" sodipodi:docname="twitter_bootstrap_logo.svg" inkscape:version="0.48.1 r9760" xmlns:svg="http://www.w3.org/2000/svg" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:cc="http://creativecommons.org/ns#" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape">
-	<g id="bg_1_">
-		<path fill="#FFFFFF" d="M510,186c25.5,0,49.6,10,67.8,28.2S606,256.5,606,282v408c0,25.5-10,49.6-28.2,67.8S535.5,786,510,786H102
-			c-25.5,0-49.6-10-67.8-28.2S6,715.5,6,690V282c0-25.5,10-49.6,28.2-67.8S76.5,186,102,186H510 M510,180H102
-			C45.9,180,0,225.9,0,282v408c0,56.1,45.9,102,102,102h408c56.1,0,102-45.9,102-102V282C612,225.9,566.1,180,510,180L510,180z"/>
-	</g>
-	<g id="B_2_" enable-background="new    ">
-		<path fill="#FFFFFF" d="M166.3,313h173.5c32,0,57.7,7.3,77,22s29,36.8,29,66.5c0,18-4.4,33.4-13.2,46.2
-			c-8.8,12.8-21.4,22.8-37.8,29.8v1c22,4.7,38.7,15.1,50,31.2c11.3,16.2,17,36.4,17,60.8c0,14-2.5,27.1-7.5,39.2
-			c-5,12.2-12.8,22.7-23.5,31.5s-24.3,15.8-41,21s-36.5,7.8-59.5,7.8h-164L166.3,313L166.3,313z M228.8,462.5h102
-			c15,0,27.5-4.2,37.5-12.8s15-20.8,15-36.8c0-18-4.5-30.7-13.5-38s-22-11-39-11h-102L228.8,462.5L228.8,462.5z M228.8,619h110.5
-			c19,0,33.8-4.9,44.2-14.8c10.5-9.8,15.8-23.8,15.8-41.8c0-17.7-5.2-31.2-15.8-40.8s-25.2-14.2-44.2-14.2H228.8V619z"/>
-	</g>
-</g>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 180 612 612">
+  <g fill="#FFF" sodipodi:docname="twitter_bootstrap_logo.svg" inkscape:version="0.48.1 r9760" xmlns:svg="http://www.w3.org/2000/svg" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:cc="http://creativecommons.org/ns#" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape">
+    <path d="M510 186c25.5 0 49.6 10 67.8 28.2S606 256.5 606 282v408c0 25.5-10 49.6-28.2 67.8S535.5 786 510 786H102c-25.5 0-49.6-10-67.8-28.2S6 715.5 6 690V282c0-25.5 10-49.6 28.2-67.8S76.5 186 102 186h408m0-6H102C45.9 180 0 225.9 0 282v408c0 56.1 45.9 102 102 102h408c56.1 0 102-45.9 102-102V282c0-56.1-45.9-102-102-102z"/>
+    <path d="M166.3 313h173.5c32 0 57.7 7.3 77 22s29 36.8 29 66.5c0 18-4.4 33.4-13.2 46.2-8.8 12.8-21.4 22.8-37.8 29.8v1c22 4.7 38.7 15.1 50 31.2 11.3 16.2 17 36.4 17 60.8 0 14-2.5 27.1-7.5 39.2-5 12.2-12.8 22.7-23.5 31.5s-24.3 15.8-41 21-36.5 7.8-59.5 7.8h-164V313zm62.5 149.5h102c15 0 27.5-4.2 37.5-12.8s15-20.8 15-36.8c0-18-4.5-30.7-13.5-38s-22-11-39-11h-102v98.6zm0 156.5h110.5c19 0 33.8-4.9 44.2-14.8 10.5-9.8 15.8-23.8 15.8-41.8 0-17.7-5.2-31.2-15.8-40.8s-25.2-14.2-44.2-14.2H228.8V619z"/>
+  </g>
 </svg>
diff --git a/assets/brand/bootstrap-punchout.svg b/assets/brand/bootstrap-punchout.svg
index 7368058bc..8dd9005d3 100644
--- a/assets/brand/bootstrap-punchout.svg
+++ b/assets/brand/bootstrap-punchout.svg
@@ -1,18 +1,6 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- Generator: Adobe Illustrator 17.1.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
-<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
-<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
-	 viewBox="0 180 612 612" enable-background="new 0 180 612 612" xml:space="preserve">
-<g id="punchout" sodipodi:docname="twitter_bootstrap_logo.svg" inkscape:version="0.48.1 r9760" xmlns:svg="http://www.w3.org/2000/svg" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:cc="http://creativecommons.org/ns#" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape">
-	<g>
-		<path fill="#FFFFFF" d="M383.5,521.8c-10.5-9.5-25.2-14.2-44.2-14.2H228.8V619h110.5c19,0,33.8-4.9,44.2-14.8
-			c10.5-9.8,15.8-23.8,15.8-41.8C399.2,544.8,394,531.2,383.5,521.8z"/>
-		<path fill="#FFFFFF" d="M368.2,449.8c10-8.5,15-20.8,15-36.8c0-18-4.5-30.7-13.5-38s-22-11-39-11h-102v98.5h102
-			C345.7,462.5,358.2,458.2,368.2,449.8z"/>
-		<path fill="#FFFFFF" d="M510,180H102C45.9,180,0,225.9,0,282v408c0,56.1,45.9,102,102,102h408c56.1,0,102-45.9,102-102V282
-			C612,225.9,566.1,180,510,180z M454.2,609.8c-5,12.2-12.8,22.7-23.5,31.5s-24.3,15.8-41,21s-36.5,7.8-59.5,7.8h-164V313h173.5
-			c32,0,57.7,7.3,77,22s29,36.8,29,66.5c0,18-4.4,33.4-13.2,46.2c-8.8,12.8-21.4,22.8-37.8,29.8v1c22,4.7,38.7,15.1,50,31.2
-			c11.3,16.2,17,36.4,17,60.8C461.7,584.5,459.2,597.6,454.2,609.8z"/>
-	</g>
-</g>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 180 612 612">
+  <g fill="#FFF" sodipodi:docname="twitter_bootstrap_logo.svg" inkscape:version="0.48.1 r9760" xmlns:svg="http://www.w3.org/2000/svg" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:cc="http://creativecommons.org/ns#" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape">
+    <path d="M383.5 521.8c-10.5-9.5-25.2-14.2-44.2-14.2H228.8V619h110.5c19 0 33.8-4.9 44.2-14.8 10.5-9.8 15.8-23.8 15.8-41.8-.1-17.6-5.3-31.2-15.8-40.6zm-15.3-72c10-8.5 15-20.8 15-36.8 0-18-4.5-30.7-13.5-38s-22-11-39-11h-102v98.5h102c15 0 27.5-4.3 37.5-12.7z"/>
+    <path d="M510 180H102C45.9 180 0 225.9 0 282v408c0 56.1 45.9 102 102 102h408c56.1 0 102-45.9 102-102V282c0-56.1-45.9-102-102-102zm-55.8 429.8c-5 12.2-12.8 22.7-23.5 31.5s-24.3 15.8-41 21-36.5 7.8-59.5 7.8h-164V313h173.5c32 0 57.7 7.3 77 22s29 36.8 29 66.5c0 18-4.4 33.4-13.2 46.2-8.8 12.8-21.4 22.8-37.8 29.8v1c22 4.7 38.7 15.1 50 31.2 11.3 16.2 17 36.4 17 60.8 0 14-2.5 27.1-7.5 39.3z"/>
+  </g>
 </svg>
diff --git a/assets/brand/bootstrap-social-logo.png b/assets/brand/bootstrap-social-logo.png
index a2f0168c5..97a7d87b7 100644
--- a/assets/brand/bootstrap-social-logo.png
+++ b/assets/brand/bootstrap-social-logo.png
diff --git a/assets/brand/bootstrap-social.png b/assets/brand/bootstrap-social.png
index cfac9c5fc..26c7ac9cc 100644
--- a/assets/brand/bootstrap-social.png
+++ b/assets/brand/bootstrap-social.png
diff --git a/assets/brand/bootstrap-solid.svg b/assets/brand/bootstrap-solid.svg
index 6c2211d86..b624a0247 100644
--- a/assets/brand/bootstrap-solid.svg
+++ b/assets/brand/bootstrap-solid.svg
@@ -1,17 +1,6 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- Generator: Adobe Illustrator 17.1.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
-<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
-<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
-	 viewBox="0 0 612 612" enable-background="new 0 0 612 612" xml:space="preserve">
-<g id="solid" sodipodi:docname="twitter_bootstrap_logo.svg" inkscape:version="0.48.1 r9760" xmlns:svg="http://www.w3.org/2000/svg" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:cc="http://creativecommons.org/ns#" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape">
-	<path id="bg" fill="#563D7C" d="M612,510c0,56.1-45.9,102-102,102H102C45.9,612,0,566.1,0,510V102C0,45.9,45.9,0,102,0h408
-		c56.1,0,102,45.9,102,102V510z"/>
-	<g id="B" enable-background="new    ">
-		<path fill="#FFFFFF" d="M166.3,133h173.5c32,0,57.7,7.3,77,22s29,36.8,29,66.5c0,18-4.4,33.4-13.2,46.2
-			c-8.8,12.8-21.4,22.8-37.8,29.8v1c22,4.7,38.7,15.1,50,31.2c11.3,16.2,17,36.4,17,60.8c0,14-2.5,27.1-7.5,39.2
-			c-5,12.2-12.8,22.7-23.5,31.5s-24.3,15.8-41,21s-36.5,7.8-59.5,7.8h-164L166.3,133L166.3,133z M228.8,282.5h102
-			c15,0,27.5-4.2,37.5-12.8s15-20.8,15-36.8c0-18-4.5-30.7-13.5-38s-22-11-39-11h-102L228.8,282.5L228.8,282.5z M228.8,439h110.5
-			c19,0,33.8-4.9,44.2-14.8c10.5-9.8,15.8-23.8,15.8-41.8c0-17.7-5.2-31.2-15.8-40.8s-25.2-14.2-44.2-14.2H228.8V439z"/>
-	</g>
-</g>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 612 612">
+  <g sodipodi:docname="twitter_bootstrap_logo.svg" inkscape:version="0.48.1 r9760" xmlns:svg="http://www.w3.org/2000/svg" xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:cc="http://creativecommons.org/ns#" xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape">
+    <path fill="#563D7C" d="M612 510c0 56.1-45.9 102-102 102H102C45.9 612 0 566.1 0 510V102C0 45.9 45.9 0 102 0h408c56.1 0 102 45.9 102 102v408z"/>
+    <path fill="#FFF" d="M166.3 133h173.5c32 0 57.7 7.3 77 22s29 36.8 29 66.5c0 18-4.4 33.4-13.2 46.2-8.8 12.8-21.4 22.8-37.8 29.8v1c22 4.7 38.7 15.1 50 31.2 11.3 16.2 17 36.4 17 60.8 0 14-2.5 27.1-7.5 39.2-5 12.2-12.8 22.7-23.5 31.5s-24.3 15.8-41 21-36.5 7.8-59.5 7.8h-164V133zm62.5 149.5h102c15 0 27.5-4.2 37.5-12.8s15-20.8 15-36.8c0-18-4.5-30.7-13.5-38s-22-11-39-11h-102v98.6zm0 156.5h110.5c19 0 33.8-4.9 44.2-14.8 10.5-9.8 15.8-23.8 15.8-41.8 0-17.7-5.2-31.2-15.8-40.8s-25.2-14.2-44.2-14.2H228.8V439z"/>
+  </g>
 </svg>
diff --git a/build/stamp.js b/build/stamp.js
index b76086f1d..f1868d879 100644
--- a/build/stamp.js
+++ b/build/stamp.js
@@ -29,7 +29,7 @@ if (typeof jQuery === 'undefined') {
 (function () {
 `
   const stampEnd = `
-})()`
+})();`
 
   process.stdout.write(stampTop)
 
diff --git a/docs/4.0/components/list-group.md b/docs/4.0/components/list-group.md
index da23ceba6..4fea041f7 100644
--- a/docs/4.0/components/list-group.md
+++ b/docs/4.0/components/list-group.md
@@ -169,10 +169,10 @@ Use the tab JavaScript plugin—include it individually or through the compiled
   <div class="row">
     <div class="col-4">
       <div class="list-group" id="list-tab" role="tablist">
-        <a class="list-group-item list-group-item-action active" id="list-home-list" data-toggle="tab" href="#list-home" role="tab" aria-controls="home">Home</a>
-        <a class="list-group-item list-group-item-action" id="list-profile-list" data-toggle="tab" href="#list-profile" role="tab" aria-controls="profile">Profile</a>
-        <a class="list-group-item list-group-item-action" id="list-messages-list" data-toggle="tab" href="#list-messages" role="tab" aria-controls="messages">Messages</a>
-        <a class="list-group-item list-group-item-action" id="list-settings-list" data-toggle="tab" href="#list-settings" role="tab" aria-controls="settings">Settings</a>
+        <a class="list-group-item list-group-item-action active" id="list-home-list" data-toggle="tab" href="#list-home" role="tab" aria-controls="list-home">Home</a>
+        <a class="list-group-item list-group-item-action" id="list-profile-list" data-toggle="tab" href="#list-profile" role="tab" aria-controls="list-profile">Profile</a>
+        <a class="list-group-item list-group-item-action" id="list-messages-list" data-toggle="tab" href="#list-messages" role="tab" aria-controls="list-messages">Messages</a>
+        <a class="list-group-item list-group-item-action" id="list-settings-list" data-toggle="tab" href="#list-settings" role="tab" aria-controls="list-settings">Settings</a>
       </div>
     </div>
     <div class="col-8">
diff --git a/index.html b/index.html
index 723a95346..f28f4ce16 100644
--- a/index.html
+++ b/index.html
@@ -107,7 +107,7 @@ layout: home
     <div class="row bd-featured-sites">
     {% for showcase in site.data.showcase %}
       <div class="col-6 col-sm-3">
-        <a href="{{ showcase.expo_url }}" target="_blank" title="{{ showcase.name }}">
+        <a href="{{ showcase.expo_url }}" target="_blank" rel="noopener" title="{{ showcase.name }}">
           <img src="{{ site.baseurl }}/assets/img/expo-{{ showcase.img }}.jpg" alt="{{ showcase.name }}" class="img-fluid">
         </a>
       </div>