diff --git a/.env.example b/.env.example
index 7f06308..7b9a801 100644
--- a/.env.example
+++ b/.env.example
@@ -2,6 +2,7 @@ APP_NAME=CoreCore
 APP_URL=http://localhost:8080
 APP_ENV=dev
 APP_DEBUG=true
+APP_VENDOR_PHP_ISSUES_MODE=suppress_deprecations
 APP_CONFIG_VALIDATE=true
 APP_TIMEZONE=Europe/Berlin
 APP_STORAGE_PATH=./storage
diff --git a/.env.prod.example b/.env.prod.example
index 3076456..5b57ff9 100644
--- a/.env.prod.example
+++ b/.env.prod.example
@@ -2,6 +2,7 @@ APP_NAME=CoreCore
 APP_URL=https://example.com
 APP_ENV=prod
 APP_DEBUG=false
+APP_VENDOR_PHP_ISSUES_MODE=strict
 APP_CONFIG_VALIDATE=true
 APP_TIMEZONE=Europe/Berlin
 APP_STORAGE_PATH=./storage
diff --git a/lib/App/Bootstrap/EnvValidator.php b/lib/App/Bootstrap/EnvValidator.php
index 2b0323d..2c0859e 100644
--- a/lib/App/Bootstrap/EnvValidator.php
+++ b/lib/App/Bootstrap/EnvValidator.php
@@ -36,7 +36,7 @@ final class EnvValidator
         }
 
         $env = [];
-        foreach (array_merge(self::REQUIRED_KEYS, ['APP_URL', 'APP_CRYPTO_KEY']) as $key) {
+        foreach (array_merge(self::REQUIRED_KEYS, ['APP_URL', 'APP_CRYPTO_KEY', 'APP_VENDOR_PHP_ISSUES_MODE']) as $key) {
             $env[$key] = getenv($key);
         }
 
@@ -97,6 +97,14 @@ final class EnvValidator
             $errors[] = "TENANT_SCOPE_STRICT must be a boolean value (true/false/1/0)";
         }
 
+        $vendorPhpIssuesMode = strtolower(self::value($env, 'APP_VENDOR_PHP_ISSUES_MODE'));
+        if (
+            $vendorPhpIssuesMode !== ''
+            && !in_array($vendorPhpIssuesMode, ['strict', 'suppress_deprecations', 'suppress_deprecations_warnings'], true)
+        ) {
+            $errors[] = 'APP_VENDOR_PHP_ISSUES_MODE must be one of: strict, suppress_deprecations, suppress_deprecations_warnings';
+        }
+
         $reverseProxy = self::value($env, 'FIREWALL_REVERSE_PROXY');
         if ($reverseProxy !== '' && self::parseBool($reverseProxy) === null) {
             $errors[] = "FIREWALL_REVERSE_PROXY must be a boolean value (true/false/1/0)";
diff --git a/lib/Http/ErrorDataCollector.php b/lib/Http/ErrorDataCollector.php
index 4fe2046..b507d8d 100644
--- a/lib/Http/ErrorDataCollector.php
+++ b/lib/Http/ErrorDataCollector.php
@@ -30,6 +30,7 @@ final class ErrorDataCollector
         'APP_TIMEZONE',
         'APP_LOCALE',
         'APP_URL',
+        'APP_VENDOR_PHP_ISSUES_MODE',
         'TENANT_SCOPE_STRICT',
     ];
 
diff --git a/lib/Http/ErrorHandler.php b/lib/Http/ErrorHandler.php
index c146b73..73b9775 100644
--- a/lib/Http/ErrorHandler.php
+++ b/lib/Http/ErrorHandler.php
@@ -96,6 +96,10 @@ final class ErrorHandler
             return true;
         }
 
+        if (self::shouldSuppressVendorIssue($severity, $file)) {
+            return true;
+        }
+
         throw new \ErrorException($message, 0, $severity, $file, $line);
     }
 
@@ -194,4 +198,46 @@ final class ErrorHandler
     {
         return defined('PHPUNIT_COMPOSER_INSTALL') || defined('__PHPUNIT_PHAR__');
     }
+
+    private static function shouldSuppressVendorIssue(int $severity, string $file): bool
+    {
+        if (!self::isVendorPath($file)) {
+            return false;
+        }
+
+        return match (self::vendorIssueMode()) {
+            'suppress_deprecations' => self::isDeprecationSeverity($severity),
+            'suppress_deprecations_warnings' => self::isDeprecationSeverity($severity) || self::isWarningSeverity($severity),
+            default => false,
+        };
+    }
+
+    private static function vendorIssueMode(): string
+    {
+        $raw = getenv('APP_VENDOR_PHP_ISSUES_MODE');
+        if ($raw === false) {
+            return 'strict';
+        }
+
+        $mode = strtolower(trim((string) $raw));
+        return in_array($mode, ['strict', 'suppress_deprecations', 'suppress_deprecations_warnings'], true)
+            ? $mode
+            : 'strict';
+    }
+
+    private static function isDeprecationSeverity(int $severity): bool
+    {
+        return in_array($severity, [E_DEPRECATED, E_USER_DEPRECATED], true);
+    }
+
+    private static function isWarningSeverity(int $severity): bool
+    {
+        return in_array($severity, [E_WARNING, E_USER_WARNING], true);
+    }
+
+    private static function isVendorPath(string $file): bool
+    {
+        $normalized = str_replace('\\', '/', $file);
+        return str_contains($normalized, '/vendor/');
+    }
 }
diff --git a/pages/admin/tenants/_form.phtml b/pages/admin/tenants/_form.phtml
index 081e85d..1067c51 100644
--- a/pages/admin/tenants/_form.phtml
+++ b/pages/admin/tenants/_form.phtml
@@ -713,6 +713,7 @@ $openOverrideCard = $detailsOpenAll;
         $openLdapSetupCard = $detailsOpenAll || !$ldapEnabled || ($ldapEnabled && !$ldapConfigComplete);
         ?>
         <hr>
+        <div data-tenant-ldap-root>
         <h4><?php e(t('LDAP Authentication')); ?></h4>
 
         <div class="app-form-info-tiles">
@@ -747,9 +748,11 @@ $openOverrideCard = $detailsOpenAll;
           <div class="app-details-card-container">
             <label class="app-field">
               <input type="checkbox" role="switch" name="ldap_enabled" value="1"
+                data-tenant-ldap-enabled
                 <?php e($ldapEnabled ? 'checked' : ''); ?> <?php e($disabledAttr); ?>>
               <span><?php e(t('Enable LDAP login for this tenant')); ?></span>
             </label>
+            <div data-tenant-ldap-when-enabled>
             <hr>
             <div class="grid grid-1-1">
               <label>
diff --git a/tests/App/Bootstrap/EnvValidatorTest.php b/tests/App/Bootstrap/EnvValidatorTest.php
index a473398..9deba7d 100644
--- a/tests/App/Bootstrap/EnvValidatorTest.php
+++ b/tests/App/Bootstrap/EnvValidatorTest.php
@@ -113,6 +113,27 @@ final class EnvValidatorTest extends TestCase
         $this->assertContains('APP_URL must not use localhost or an IP host in production', $errors);
     }
 
+    public function testValidateArrayAcceptsSupportedVendorPhpIssuesMode(): void
+    {
+        $errors = EnvValidator::validateArray($this->baseEnv([
+            'APP_VENDOR_PHP_ISSUES_MODE' => 'suppress_deprecations',
+        ]));
+
+        $this->assertSame([], $errors);
+    }
+
+    public function testValidateArrayRejectsUnsupportedVendorPhpIssuesMode(): void
+    {
+        $errors = EnvValidator::validateArray($this->baseEnv([
+            'APP_VENDOR_PHP_ISSUES_MODE' => 'disable_everything',
+        ]));
+
+        $this->assertContains(
+            'APP_VENDOR_PHP_ISSUES_MODE must be one of: strict, suppress_deprecations, suppress_deprecations_warnings',
+            $errors
+        );
+    }
+
     /**
      * @param array<string, string> $override
      * @return array<string, string>
@@ -125,6 +146,7 @@ final class EnvValidatorTest extends TestCase
             'APP_NAME' => 'CoreCore',
             'APP_ENV' => 'dev',
             'APP_DEBUG' => 'true',
+            'APP_VENDOR_PHP_ISSUES_MODE' => 'strict',
             'APP_TIMEZONE' => 'Europe/Berlin',
             'APP_STORAGE_PATH' => $storagePath,
             'APP_LOCALE' => 'de',
diff --git a/tests/Http/ErrorHandlerTest.php b/tests/Http/ErrorHandlerTest.php
index 9e3d673..e9871c9 100644
--- a/tests/Http/ErrorHandlerTest.php
+++ b/tests/Http/ErrorHandlerTest.php
@@ -10,10 +10,15 @@ use PHPUnit\Framework\TestCase;
 class ErrorHandlerTest extends TestCase
 {
     private array $serverBackup = [];
+    private int $errorReportingBackup = 0;
+    private string|false $vendorIssueModeBackup = false;
 
     protected function setUp(): void
     {
         $this->serverBackup = $_SERVER;
+        $this->errorReportingBackup = error_reporting();
+        error_reporting(E_ALL);
+        $this->vendorIssueModeBackup = getenv('APP_VENDOR_PHP_ISSUES_MODE');
         RequestContext::resetForTests();
         Debugger::$enabled = false;
         header_remove();
@@ -23,6 +28,12 @@ class ErrorHandlerTest extends TestCase
     protected function tearDown(): void
     {
         $_SERVER = $this->serverBackup;
+        error_reporting($this->errorReportingBackup);
+        if ($this->vendorIssueModeBackup === false) {
+            putenv('APP_VENDOR_PHP_ISSUES_MODE');
+        } else {
+            putenv('APP_VENDOR_PHP_ISSUES_MODE=' . $this->vendorIssueModeBackup);
+        }
         RequestContext::resetForTests();
         Debugger::$enabled = false;
         header_remove();
@@ -75,4 +86,44 @@ class ErrorHandlerTest extends TestCase
 
         $this->assertSame(500, http_response_code());
     }
+
+    public function testHandleErrorThrowsForVendorDeprecationInStrictMode(): void
+    {
+        putenv('APP_VENDOR_PHP_ISSUES_MODE=strict');
+
+        $this->expectException(\ErrorException::class);
+        ErrorHandler::handleError(E_DEPRECATED, 'deprecated', '/var/www/vendor/mintyphp/core/src/Router.php', 69);
+    }
+
+    public function testHandleErrorSuppressesVendorDeprecationsWhenConfigured(): void
+    {
+        putenv('APP_VENDOR_PHP_ISSUES_MODE=suppress_deprecations');
+
+        $result = ErrorHandler::handleError(E_DEPRECATED, 'deprecated', '/var/www/vendor/mintyphp/core/src/Router.php', 69);
+        $this->assertTrue($result);
+    }
+
+    public function testHandleErrorSuppressesVendorWarningsOnlyInWarningMode(): void
+    {
+        putenv('APP_VENDOR_PHP_ISSUES_MODE=suppress_deprecations');
+
+        try {
+            ErrorHandler::handleError(E_WARNING, 'warning', '/var/www/vendor/mintyphp/core/src/Router.php', 69);
+            $this->fail('Expected ErrorException for vendor warning in suppress_deprecations mode.');
+        } catch (\ErrorException) {
+            // expected
+        }
+
+        putenv('APP_VENDOR_PHP_ISSUES_MODE=suppress_deprecations_warnings');
+        $result = ErrorHandler::handleError(E_WARNING, 'warning', '/var/www/vendor/mintyphp/core/src/Router.php', 69);
+        $this->assertTrue($result);
+    }
+
+    public function testHandleErrorNeverSuppressesNonVendorWarnings(): void
+    {
+        putenv('APP_VENDOR_PHP_ISSUES_MODE=suppress_deprecations_warnings');
+
+        $this->expectException(\ErrorException::class);
+        ErrorHandler::handleError(E_WARNING, 'warning', '/var/www/lib/Http/ErrorHandler.php', 69);
+    }
 }