diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
index 24467d87..dc07f8e6 100644
--- a/.github/workflows/test.yaml
+++ b/.github/workflows/test.yaml
@@ -15,12 +15,8 @@ jobs:
                     - 7.3
                     - 7.4
                     - 8.0
-                phpunit: [8.5]
+                    - 8.1
                 dependencies: [highest]
-                include:
-                    - php-version: 7.1
-                      phpunit: 7.5
-                      dependencies: lowest
 
         steps:
             - name: Checkout
@@ -41,4 +37,4 @@ jobs:
                   composer-options: --prefer-dist
 
             - name: Run Tests
-              run: SYMFONY_PHPUNIT_VERSION=${{ matrix.phpunit }} vendor/bin/simple-phpunit
+              run: vendor/bin/simple-phpunit
diff --git a/composer.json b/composer.json
index 99b69a2e..3e37a512 100644
--- a/composer.json
+++ b/composer.json
@@ -20,18 +20,18 @@
         "php": "^7.1|^8.0",
         "ext-zip": "*",
         "ext-json": "*",
-        "symfony/asset": "^4.4 || ^5.0",
-        "symfony/config": "^4.4 || ^5.0",
-        "symfony/dependency-injection": "^4.4 || ^5.0",
-        "symfony/expression-language": "^4.4 || ^5.0",
-        "symfony/form": "^4.4 || ^5.0",
-        "symfony/framework-bundle": "^4.4 || ^5.0",
-        "symfony/http-foundation": "^4.4 || ^5.0",
-        "symfony/http-kernel": "^4.4 || ^5.0",
-        "symfony/options-resolver": "^4.4 || ^5.0",
-        "symfony/property-access": "^4.4 || ^5.0",
-        "symfony/routing": "^4.4 || ^5.0",
-        "symfony/twig-bundle": "^4.4 || ^5.0",
+        "symfony/asset": "^4.4 || ^5.0 || ^6.0",
+        "symfony/config": "^4.4 || ^5.0 || ^6.0",
+        "symfony/dependency-injection": "^4.4 || ^5.0 || ^6.0",
+        "symfony/expression-language": "^4.4 || ^5.0 || ^6.0",
+        "symfony/form": "^4.4 || ^5.0 || ^6.0",
+        "symfony/framework-bundle": "^4.4 || ^5.0 || ^6.0",
+        "symfony/http-foundation": "^4.4 || ^5.0 || ^6.0",
+        "symfony/http-kernel": "^4.4 || ^5.0 || ^6.0",
+        "symfony/options-resolver": "^4.4 || ^5.0 || ^6.0",
+        "symfony/property-access": "^4.4 || ^5.0 || ^6.0",
+        "symfony/routing": "^4.4 || ^5.0 || ^6.0",
+        "symfony/twig-bundle": "^4.4 || ^5.0 || ^6.0",
         "twig/twig": "^2.4 || ^3.0"
     },
     "conflict": {
@@ -41,9 +41,9 @@
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^2.0",
         "matthiasnoback/symfony-dependency-injection-test": "^3.0 || ^4.0",
-        "symfony/console": "^4.4 || ^5.0",
-        "symfony/phpunit-bridge": "^4.4 || ^5.0",
-        "symfony/yaml": "^4.4 || ^5.0"
+        "symfony/console": "^4.4 || ^5.0 || ^6.0",
+        "symfony/phpunit-bridge": "^4.4 || ^5.0 || ^6.0",
+        "symfony/yaml": "^4.4 || ^5.0 || ^6.0"
     },
     "suggest": {
         "egeloen/form-extra-bundle": "Allows to load CKEditor asynchronously"
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 06457f4a..ef9db803 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -5,11 +5,7 @@
     xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/6.0/phpunit.xsd"
     colors="true"
     bootstrap="tests/autoload.php">
-
-    <php>
-        <server name="SYMFONY_PHPUNIT_VERSION" value="8.5" />
-    </php>
-
+    
     <testsuites>
         <testsuite name="FOSCKEditorBundle Test Suite">
             <directory>./tests</directory>
diff --git a/src/Renderer/CKEditorRenderer.php b/src/Renderer/CKEditorRenderer.php
index acf90355..33b4ff32 100644
--- a/src/Renderer/CKEditorRenderer.php
+++ b/src/Renderer/CKEditorRenderer.php
@@ -278,7 +278,7 @@ private function getLanguage(): ?string
     {
         $request = $this->requestStack->getCurrentRequest();
 
-        if (null !== $request) {
+        if (null !== $request && '' !== $request->getLocale()) {
             return $request->getLocale();
         }
 
diff --git a/tests/Installer/CKEditorInstallerTest.php b/tests/Installer/CKEditorInstallerTest.php
index 957da333..303d0189 100644
--- a/tests/Installer/CKEditorInstallerTest.php
+++ b/tests/Installer/CKEditorInstallerTest.php
@@ -84,7 +84,7 @@ public function testInstallWithCustomBuild(): void
     public function testInstallWithCustomBuildWithInvalidVersion(): void
     {
         $this->expectException(\RuntimeException::class);
-        $this->expectExceptionMessageRegExp('/Specifying version for custom build is not supported/');
+        $this->expectExceptionMessageMatches('/Specifying version for custom build is not supported/');
 
         $this->installer->install($options = ['release' => CKEditorInstaller::RELEASE_CUSTOM, 'custom_build_id' => '459c358ccf2e34f083e3c8847d3af23e', 'version' => '4.11.4']);
     }
@@ -92,7 +92,7 @@ public function testInstallWithCustomBuildWithInvalidVersion(): void
     public function testInstallWithCustomBuildWithMissingId(): void
     {
         $this->expectException(\RuntimeException::class);
-        $this->expectExceptionMessageRegExp('/Custom build ID is not specified/');
+        $this->expectExceptionMessageMatches('/Custom build ID is not specified/');
 
         $this->installer->install($options = ['release' => CKEditorInstaller::RELEASE_CUSTOM]);
     }
diff --git a/tests/Renderer/CKEditorRendererTest.php b/tests/Renderer/CKEditorRendererTest.php
index 7a7c87d4..2f15d722 100644
--- a/tests/Renderer/CKEditorRendererTest.php
+++ b/tests/Renderer/CKEditorRendererTest.php
@@ -118,7 +118,7 @@ public function testRenderJsPath(): void
     public function testRenderWidgetWithLocaleRequest(string $symfonyLocale, string $ckEditorLocale): void
     {
         $this->request
-            ->expects($this->once())
+            ->expects($this->exactly(2))
             ->method('getLocale')
             ->will($this->returnValue($symfonyLocale));
 
@@ -133,7 +133,7 @@ public function testRenderWidgetWithLocaleRequest(string $symfonyLocale, string
      */
     public function testRenderWidgetWithLocaleParameter(string $symfonyLocale, string $ckEditorLocale): void
     {
-        $this->request->expects($this->once())->method('getLocale')->will($this->returnValue($symfonyLocale));
+        $this->request->expects($this->exactly(2))->method('getLocale')->will($this->returnValue($symfonyLocale));
         $this->assertSame(
             'CKEDITOR.replace("foo", {"language":"'.$ckEditorLocale.'"});',
             $this->renderer->renderWidget('foo', [])
@@ -156,7 +156,7 @@ public function testRenderWidgetWithoutLocale(): void
         $this->request
             ->expects($this->once())
             ->method('getLocale')
-            ->will($this->returnValue(null));
+            ->will($this->returnValue(''));
 
         $this->assertSame(
             'CKEDITOR.replace("foo", []);',