diff --git a/.travis.yml b/.travis.yml
index 295c72b..da52ba4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,6 +12,7 @@ php:
   - '7.0'
   - '7.1'
   - '7.2'
+  - '7.3'
   - nightly
 
 sudo: false
@@ -29,28 +30,28 @@ env:
 matrix:
   fast_finish: true
   include:
-    - php: '5.4'
+    - php: '5.6'
       env: COMPOSER_FLAGS="--prefer-lowest"
     - php: '7.0'
       env: SYMFONY=2.3.*
-    - php: '7.2'
+    - php: '7.0'
       env: SYMFONY=2.7.*
-    - php: '7.2'
+    - php: '7.0'
       env: SYMFONY=2.8.*
-    - php: '7.2'
-      env: SYMFONY=3.3.*
-    - php: '7.2'
+    - php: '7.3'
       env: SYMFONY=3.4.*
-    - php: '7.2'
-      env: SYMFONY=4.0.*
-    - php: '7.2'
-      env: SYMFONY='dev-master as 4.1.x-dev'
-    - php: '7.2'
+    - php: '7.3'
+      env: SYMFONY=4.1.*
+    - php: '7.3'
+      env: SYMFONY=4.2.*
+    - php: '7.3'
+      env: SYMFONY='dev-master as 4.3.x-dev'
+    - php: '7.3'
       env: SYMFONY_DEPRECATIONS_HELPER=0
   allow_failures:
     - php: nightly
     - env: SYMFONY_DEPRECATIONS_HELPER=0
-    - env: SYMFONY='dev-master as 4.1.x-dev'
+    - env: SYMFONY='dev-master as 4.3.x-dev'
 
 before_install:
   - echo memory_limit = -1 >> $HOME/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini;
diff --git a/DependencyInjection/Configuration.php b/DependencyInjection/Configuration.php
index 0426058..b71dc4c 100644
--- a/DependencyInjection/Configuration.php
+++ b/DependencyInjection/Configuration.php
@@ -25,8 +25,14 @@ class Configuration implements ConfigurationInterface
      */
     public function getConfigTreeBuilder()
     {
-        $treeBuilder = new TreeBuilder();
-        $rootNode = $treeBuilder->root('a2lix_translation_form');
+        $treeBuilder = new TreeBuilder('a2lix_translation_form');
+        
+        // Keep compatibility with symfony/config < 4.2
+        if (!method_exists($treeBuilder, 'getRootNode')) {
+            $rootNode = $treeBuilder->root('a2lix_translation_form');
+        } else {
+            $rootNode = $treeBuilder->getRootNode();
+        }
 
         $rootNode
             ->children()