diff --git a/core/modules/color/color.module b/core/modules/color/color.module
index 3cae045..0f567dc 100644
--- a/core/modules/color/color.module
+++ b/core/modules/color/color.module
@@ -300,8 +300,8 @@ function template_preprocess_color_scheme_form(&$variables) {
   }
 
   // Attempt to load preview HTML if the theme provides it.
-  $preview_html_path = \Drupal::root() . '/' . (isset($info['preview_html']) ? drupal_get_path('theme', $theme) . '/' . $info['preview_html'] : drupal_get_path('module', 'color') . '/preview.html');
-  $variables['html_preview']['#markup'] = file_get_contents($preview_html_path);
+  $preview_html_path = isset($info['preview_html']) ? drupal_get_path('theme', $theme) . '/' . $info['preview_html'] : drupal_get_path('module', 'color') . '/preview.html.twig';
+  $variables['html_preview']['#markup'] = \Drupal::service('twig')->loadTemplate($preview_html_path, NULL)->render(array());
 }
 
 /**
diff --git a/core/modules/color/preview.html b/core/modules/color/preview.html
deleted file mode 100644
index d89edcb..0000000
--- a/core/modules/color/preview.html
+++ /dev/null
@@ -1,7 +0,0 @@
-<div class="color-preview">
-  <div id="text">
-    <h2>Lorem ipsum dolor</h2>
-    <p>Sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud <a href="#">exercitation ullamco</a> laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p>
-  </div>
-  <div id="img"></div>
-</div>
diff --git a/core/modules/color/preview.html.twig b/core/modules/color/preview.html.twig
new file mode 100644
index 0000000..55f14fd
--- /dev/null
+++ b/core/modules/color/preview.html.twig
@@ -0,0 +1,16 @@
+<div class="color-preview">
+  <div id="text">
+    <h2>
+      {% trans %} Example heading {% endtrans %}
+    </h2>
+    <p>
+        {% trans %} This is a block of example content. This content is here to
+      demonstrate what actual content would look like in the color scheme you
+      configure. <a href="#">This is an example link</a>, to demonstrate how
+      background colors you configure may affect the readability of links. This
+      is some more text to demonstrate what actual content would
+      look like in the color scheme you configure. {% endtrans %}
+    </p>
+  </div>
+  <div id="img"></div>
+</div>
diff --git a/core/themes/bartik/color/color.inc b/core/themes/bartik/color/color.inc
index 4f42620..a25f36c 100644
--- a/core/themes/bartik/color/color.inc
+++ b/core/themes/bartik/color/color.inc
@@ -116,7 +116,7 @@
 
   // Preview files.
   'preview_library' => 'bartik/color.preview',
-  'preview_html' => 'color/preview.html',
+  'preview_html' => 'color/preview.html.twig',
 
   // Attachments.
   '#attached' => [
diff --git a/core/themes/bartik/color/preview.html b/core/themes/bartik/color/preview.html
deleted file mode 100644
index 7031b08..0000000
--- a/core/themes/bartik/color/preview.html
+++ /dev/null
@@ -1,65 +0,0 @@
-<div class="color-preview">
-
-  <div class="color-preview-header">
-    <div class="color-preview-logo"><img src="../../../core/themes/bartik/logo.svg" alt="Site Logo" /></div>
-    <div class="color-preview-site-name">Bartik</div>
-    <div class="color-preview-main-menu">
-      <ul class="color-preview-main-menu-links">
-        <li><a>Home</a></li>
-        <li><a>Te Quidne</a></li>
-        <li><a>Vel Torqueo Quae Erat</a></li>
-      </ul>
-    </div>
-  </div>
-
-  <div class="color-preview-main clearfix">
-    <div class="color-preview-sidebar">
-      <div class="color-preview-block preview-block">
-        <h2>Etiam est risus</h2>
-        <div class="preview-content">
-          Maecenas id porttitor Ut enim ad minim veniam, quis nostrudfelis.
-          Laboris nisi ut aliquip ex ea.
-        </div>
-      </div>
-    </div>
-    <div class="color-preview-content">
-      <h1 class="color-preview-page-title">Lorem ipsum dolor</h1>
-      <div class="color-preview-node">
-        <div class="preview-content">
-          Sit amet, <a>consectetur adipisicing elit</a>, sed do eiusmod tempor
-          incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis
-          nostrud <a>exercitation ullamco</a> laboris nisi ut aliquip ex ea
-          commodo consequat. Maecenas id porttitor Ut enim ad minim veniam, quis nostr udfelis.
-        </div>
-      </div>
-    </div>
-  </div>
-
-  <div class="color-preview-footer-wrapper">
-    <div class="color-preview-footer-columns clearfix">
-      <div class="preview-footer-column">
-        <div class="preview-block">
-          <h2>Etiam est risus</h2>
-          <div class="content">
-            Maecenas id porttitor Ut enim ad minim veniam, quis nostrudfelis.
-            Laboris nisi ut aliquip ex ea.
-          </div>
-        </div>
-      </div>
-      <div class="preview-footer-column">
-        <div class="preview-block preview-block-menu">
-          <h2>Erisus dolor</h2>
-          <div class="preview-content">
-            <ul>
-              <li><a>Donec placerat</a></li>
-              <li><a>Nullam nibh dolor</a></li>
-              <li><a>Blandit sed</a></li>
-              <li><a>Fermentum id</a></li>
-            </ul>
-          </div>
-        </div>
-      </div>
-    </div>
-  </div>
-
-</div>
diff --git a/core/themes/bartik/color/preview.html.twig b/core/themes/bartik/color/preview.html.twig
new file mode 100644
index 0000000..53eba06
--- /dev/null
+++ b/core/themes/bartik/color/preview.html.twig
@@ -0,0 +1,75 @@
+<div class="color-preview">
+
+  <div class="color-preview-header">
+    <div class="color-preview-logo"><img
+              src="../../../core/themes/bartik/logo.svg" alt="Site Logo"/>
+    </div>
+    <div class="color-preview-site-name">{% trans %} Bartik {% endtrans %}</div>
+    <div class="color-preview-main-menu">
+      <ul class="color-preview-main-menu-links">
+        <li><a>{% trans %} Tab One {% endtrans %}</a></li>
+        <li><a>{% trans %} Tab Two {% endtrans %}</a></li>
+        <li><a>{% trans %} Tab Three {% endtrans %}</a></li>
+      </ul>
+    </div>
+  </div>
+
+  <div class="color-preview-main clearfix">
+    <div class="color-preview-sidebar">
+      <div class="color-preview-block preview-block">
+        <h2>{% trans %} Example heading {% endtrans %}</h2>
+        <div class="preview-content">
+          {% trans %} This is a block of example content. This content is here
+          to demonstrate what actual content would look like in the color scheme
+          you configure. {% endtrans %}
+        </div>
+      </div>
+    </div>
+    <div class="color-preview-content">
+      <h1 class="color-preview-page-title">{% trans %}
+        This is an example heading {% endtrans %}
+      </h1>
+      <div class="color-preview-node">
+        <div class="preview-content">
+          {% trans %} This is a block of example content. This content is here
+          to demonstrate what actual content would look like in the color
+          scheme you configure. <a href="#">This is an example link</a>, to
+          demonstrate how background colors you configure may affect the
+          readability of links. Another sentence to demonstrate what actual
+          content would look like in the color scheme you configure.
+          <a href="#">This is another example link.</a> This is the end of this
+          block of example content. {% endtrans %}
+        </div>
+      </div>
+    </div>
+  </div>
+
+  <div class="color-preview-footer-wrapper">
+    <div class="color-preview-footer-columns clearfix">
+      <div class="preview-footer-column">
+        <div class="preview-block">
+          <h2>{% trans %} Example heading {% endtrans %}</h2>
+          <div class="content">
+            {% trans %} This is a block of example content. This content is here
+            to demonstrate what actual content would look like
+            in the color scheme you configure. {% endtrans %}
+          </div>
+        </div>
+      </div>
+      <div class="preview-footer-column">
+        <div class="preview-block preview-block-menu">
+          <h2>{% trans %} Example heading {% endtrans %}</h2>
+          <div class="preview-content">
+            <ul>
+              <li><a>{% trans %} Footer link one {% endtrans %}</a></li>
+              <li><a>{% trans %} Footer link two {% endtrans %}</a></li>
+              <li><a>{% trans %} Footer link three {% endtrans %}</a></li>
+              <li><a>{% trans %} Footer link four {% endtrans %}</a></li>
+            </ul>
+          </div>
+        </div>
+      </div>
+    </div>
+  </div>
+
+</div>
diff --git a/sites/default/default.settings.php b/sites/default/default.settings.php
index 25d498e..30deff4 100644
--- a/sites/default/default.settings.php
+++ b/sites/default/default.settings.php
@@ -144,11 +144,6 @@
  * @code
  *   'prefix' => 'main_',
  * @endcode
- *
- * Per-table prefixes are deprecated as of Drupal 8.2, and will be removed in
- * Drupal 9.0. After that, only a single prefix for all tables will be
- * supported.
- *
  * To provide prefixes for specific tables, set 'prefix' as an array.
  * The array's keys are the table names and the values are the prefixes.
  * The 'default' element is mandatory and holds the prefix for any tables
@@ -270,11 +265,6 @@
  * by the user.
  *
  * @see install_select_profile()
- *
- * @deprecated in Drupal 8.3.0 and will be removed before Drupal 9.0.0. The
- *   install profile is written to the core.extension configuration. If a
- *   service requires the install profile use the 'install_profile' container
- *   parameter. Functional code can use \Drupal::installProfile().
  */
 # $settings['install_profile'] = '';
 
