diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 000000000..0130395f0
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1 @@
+/extra/** export-ignore
diff --git a/doc/filters/data_uri.rst b/doc/filters/data_uri.rst
index feaf6de48..435c76d71 100644
--- a/doc/filters/data_uri.rst
+++ b/doc/filters/data_uri.rst
@@ -33,7 +33,7 @@ The ``data_uri`` filter generates a URL using the data scheme as defined in RFC
 
      Then, add it on the Twig environment::
 
-        use Twig\Html\HtmlExtension;
+        use Twig\Extra\Html\HtmlExtension;
 
         $twig = new \Twig\Environment(...);
         $twig->addExtension(new HtmlExtension());
diff --git a/doc/functions/html_classes.rst b/doc/functions/html_classes.rst
index 0ccf56133..e3951e0ba 100644
--- a/doc/functions/html_classes.rst
+++ b/doc/functions/html_classes.rst
@@ -26,7 +26,7 @@ names together:
 
      Then, add it on the Twig environment::
 
-        use Twig\Html\HtmlExtension;
+        use Twig\Extra\Html\HtmlExtension;
 
         $twig = new \Twig\Environment(...);
         $twig->addExtension(new HtmlExtension());
diff --git a/extra/html-extension/.gitignore b/extra/html-extra/.gitignore
similarity index 100%
rename from extra/html-extension/.gitignore
rename to extra/html-extra/.gitignore
diff --git a/extra/html-extension/LICENSE b/extra/html-extra/LICENSE
similarity index 100%
rename from extra/html-extension/LICENSE
rename to extra/html-extra/LICENSE
diff --git a/extra/html-extension/README.md b/extra/html-extra/README.md
similarity index 70%
rename from extra/html-extension/README.md
rename to extra/html-extra/README.md
index c190c14e2..e2c46b08e 100644
--- a/extra/html-extension/README.md
+++ b/extra/html-extra/README.md
@@ -9,5 +9,5 @@ This package is a Twig extension that provides the following:
  * [`html_classes`][2] function: returns a string by conditionally joining class
    names together.
 
-[1]: https://twig.symfony.com/doc/2.x/functions/html_classes.html
-[2]: https://twig.symfony.com/doc/2.x/filters/data_uri.html
+[1]: https://twig.symfony.com/data_uri
+[2]: https://twig.symfony.com/html_classes
diff --git a/extra/html-extension/composer.json b/extra/html-extra/composer.json
similarity index 89%
rename from extra/html-extension/composer.json
rename to extra/html-extra/composer.json
index 75a905213..4cc61c440 100644
--- a/extra/html-extension/composer.json
+++ b/extra/html-extra/composer.json
@@ -23,12 +23,12 @@
     },
     "autoload": {
         "psr-4" : {
-            "Twig\\Html\\" : "src/"
+            "Twig\\Extra\\Html\\" : "src/"
         }
     },
     "autoload-dev": {
         "psr-4" : {
-            "Twig\\Html\\Tests\\" : "tests/"
+            "Twig\\Extra\\Html\\Tests\\" : "tests/"
         }
     },
     "extra": {
diff --git a/extra/html-extension/phpunit.xml.dist b/extra/html-extra/phpunit.xml.dist
similarity index 100%
rename from extra/html-extension/phpunit.xml.dist
rename to extra/html-extra/phpunit.xml.dist
diff --git a/extra/html-extension/src/HtmlExtension.php b/extra/html-extra/src/HtmlExtension.php
similarity index 99%
rename from extra/html-extension/src/HtmlExtension.php
rename to extra/html-extra/src/HtmlExtension.php
index 847270ee6..65cb57011 100644
--- a/extra/html-extension/src/HtmlExtension.php
+++ b/extra/html-extra/src/HtmlExtension.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace Twig\Html {
+namespace Twig\Extra\Html {
 use Symfony\Component\Mime\MimeTypes;
 use Twig\Extension\AbstractExtension;
 use Twig\TwigFilter;
diff --git a/extra/html-extension/tests/Fixtures/data_uri.test b/extra/html-extra/tests/Fixtures/data_uri.test
similarity index 100%
rename from extra/html-extension/tests/Fixtures/data_uri.test
rename to extra/html-extra/tests/Fixtures/data_uri.test
diff --git a/extra/html-extension/tests/Fixtures/html_classes.test b/extra/html-extra/tests/Fixtures/html_classes.test
similarity index 100%
rename from extra/html-extension/tests/Fixtures/html_classes.test
rename to extra/html-extra/tests/Fixtures/html_classes.test
diff --git a/extra/html-extension/tests/Fixtures/html_classes_with_unsupported_arg.test b/extra/html-extra/tests/Fixtures/html_classes_with_unsupported_arg.test
similarity index 100%
rename from extra/html-extension/tests/Fixtures/html_classes_with_unsupported_arg.test
rename to extra/html-extra/tests/Fixtures/html_classes_with_unsupported_arg.test
diff --git a/extra/html-extension/tests/Fixtures/html_classes_with_unsupported_key.test b/extra/html-extra/tests/Fixtures/html_classes_with_unsupported_key.test
similarity index 100%
rename from extra/html-extension/tests/Fixtures/html_classes_with_unsupported_key.test
rename to extra/html-extra/tests/Fixtures/html_classes_with_unsupported_key.test
diff --git a/extra/html-extension/tests/IntegrationTest.php b/extra/html-extra/tests/IntegrationTest.php
similarity index 87%
rename from extra/html-extension/tests/IntegrationTest.php
rename to extra/html-extra/tests/IntegrationTest.php
index 3cc1f09fa..8f464c152 100644
--- a/extra/html-extension/tests/IntegrationTest.php
+++ b/extra/html-extra/tests/IntegrationTest.php
@@ -9,9 +9,9 @@
  * file that was distributed with this source code.
  */
 
-namespace Twig\Intl\Tests;
+namespace Twig\Extra\Html\Tests;
 
-use Twig\Html\HtmlExtension;
+use Twig\Extra\Html\HtmlExtension;
 use Twig\Test\IntegrationTestCase;
 
 class IntegrationTest extends IntegrationTestCase