diff --git a/phpBB/config/development/config.yml b/phpBB/config/development/config.yml
index 67c0e5a871..6f4be70a4f 100644
--- a/phpBB/config/development/config.yml
+++ b/phpBB/config/development/config.yml
@@ -3,6 +3,7 @@ imports:
 
 core:
     require_dev_dependencies: true
+    allow_install_dir: true
 
     debug:
         exceptions: true
diff --git a/phpBB/config/test/config.yml b/phpBB/config/test/config.yml
index 1c17b08931..a603f59dec 100644
--- a/phpBB/config/test/config.yml
+++ b/phpBB/config/test/config.yml
@@ -3,3 +3,4 @@ imports:
 
 core:
     require_dev_dependencies: true
+    allow_install_dir: true
diff --git a/phpBB/phpbb/di/extension/container_configuration.php b/phpBB/phpbb/di/extension/container_configuration.php
index 3a6502a4b3..67e12ed77b 100644
--- a/phpBB/phpbb/di/extension/container_configuration.php
+++ b/phpBB/phpbb/di/extension/container_configuration.php
@@ -31,6 +31,7 @@ class container_configuration implements ConfigurationInterface
 		$rootNode
 			->children()
 				->booleanNode('require_dev_dependencies')->defaultValue(false)->end()
+				->booleanNode('allow_install_dir')->defaultValue(false)->end()
 				->arrayNode('debug')
 					->addDefaultsIfNotSet()
 					->children()
diff --git a/phpBB/phpbb/di/extension/core.php b/phpBB/phpbb/di/extension/core.php
index 75a037871f..cdba25f13b 100644
--- a/phpBB/phpbb/di/extension/core.php
+++ b/phpBB/phpbb/di/extension/core.php
@@ -72,6 +72,8 @@ class core extends Extension
 			}
 		}
 
+		$container->setParameter('allow_install_dir', $config['allow_install_dir']);
+
 		// Set the Twig options if defined in the environment
 		$definition = $container->getDefinition('template.twig.environment');
 		$twig_environment_options = $definition->getArgument(static::TWIG_OPTIONS_POSITION);
diff --git a/phpBB/phpbb/user.php b/phpBB/phpbb/user.php
index 7afe31dcb8..7b6c768db8 100644
--- a/phpBB/phpbb/user.php
+++ b/phpBB/phpbb/user.php
@@ -110,7 +110,7 @@ class user extends \phpbb\session
 	function setup($lang_set = false, $style_id = false)
 	{
 		global $db, $request, $template, $config, $auth, $phpEx, $phpbb_root_path, $cache;
-		global $phpbb_dispatcher;
+		global $phpbb_dispatcher, $phpbb_container;
 
 		$this->language->set_default_language($config['default_lang']);
 
@@ -325,7 +325,7 @@ class user extends \phpbb\session
 
 		// Disable board if the install/ directory is still present
 		// For the brave development army we do not care about this, else we need to comment out this every time we develop locally
-		if (!defined('DEBUG') && !defined('ADMIN_START') && !defined('IN_INSTALL') && !defined('IN_LOGIN') && file_exists($phpbb_root_path . 'install') && !is_file($phpbb_root_path . 'install'))
+		if (!$phpbb_container->getParameter('allow_install_dir') && !defined('ADMIN_START') && !defined('IN_INSTALL') && !defined('IN_LOGIN') && file_exists($phpbb_root_path . 'install') && !is_file($phpbb_root_path . 'install'))
 		{
 			// Adjust the message slightly according to the permissions
 			if ($auth->acl_gets('a_', 'm_') || $auth->acl_getf_global('m_'))