diff --git a/api/avatar.php b/api/avatar.php
index dbe473a48b..cae76002f9 100644
--- a/api/avatar.php
+++ b/api/avatar.php
@@ -25,6 +25,9 @@ $GLOBALS['egw_info'] = array(
 
 include '../header.inc.php';
 
+// release session, as we dont need it and it blocks parallel requests
+$GLOBALS['egw']->session->commit_session();
+
 $contacts = new Api\Contacts();
 
 $contacts->photo();
\ No newline at end of file
diff --git a/api/categories.php b/api/categories.php
index 578d6f1c7b..3973f08cf1 100644
--- a/api/categories.php
+++ b/api/categories.php
@@ -26,6 +26,9 @@ $GLOBALS['egw_info'] = array(
 
 include '../header.inc.php';
 
+// release session, as we dont need it and it blocks parallel requests
+$GLOBALS['egw']->session->commit_session();
+
 // Get appname
 $appname = $_GET['app'] && $GLOBALS['egw_info']['apps'][$_GET['app']] ? $_GET['app'] : Api\Categories::GLOBAL_APPNAME;
 
diff --git a/api/config.php b/api/config.php
index 916ba4cc6f..c0dde35bb0 100644
--- a/api/config.php
+++ b/api/config.php
@@ -26,6 +26,9 @@ $GLOBALS['egw_info'] = array(
 
 include '../header.inc.php';
 
+// release session, as we dont need it and it blocks parallel requests
+$GLOBALS['egw']->session->commit_session();
+
 // use an etag over config and link-registry
 $config = json_encode(Api\Config::clientConfigs());
 $link_registry = Api\Link::json_registry();
diff --git a/api/images.php b/api/images.php
index e1d157e94e..aaa1b6878d 100644
--- a/api/images.php
+++ b/api/images.php
@@ -28,6 +28,9 @@ $GLOBALS['egw_info'] = array(
 
 include '../header.inc.php';
 
+// release session, as we dont need it and it blocks parallel requests
+$GLOBALS['egw']->session->commit_session();
+
 $content = json_encode(Api\Image::map(preg_match('/^[a-z0-9_-]+$/i',$_GET['template']) ? $_GET['template'] : null),
 	JSON_FORCE_OBJECT |	// export empty php-arrays as empty objects, not empty arrays
 	JSON_UNESCAPED_SLASHES | // do not escape slashes, smaller and better readable
diff --git a/api/lang.php b/api/lang.php
index 1984ea7195..8a27cbae23 100644
--- a/api/lang.php
+++ b/api/lang.php
@@ -37,6 +37,8 @@ catch (\EGroupware\Api\Exception\NoPermission\App $e)
 {
 	// ignore missing run rights for an app, as translations of other apps are loaded sometimes without run rights
 }
+// release session, as we dont need it and it blocks parallel requests
+$GLOBALS['egw']->session->commit_session();
 
 // use an etag with app, lang and a hash over the creation-times of all lang-files
 $etag = '"'.$_GET['app'].'-'.$_GET['lang'].'-'.  Api\Translation::etag($_GET['app'], $_GET['lang']).'"';
diff --git a/api/user.php b/api/user.php
index 64c79dd480..1bf0986580 100644
--- a/api/user.php
+++ b/api/user.php
@@ -26,6 +26,9 @@ $GLOBALS['egw_info'] = array(
 
 include '../header.inc.php';
 
+// release session, as we dont need it and it blocks parallel requests
+$GLOBALS['egw']->session->commit_session();
+
 // use an etag over config and link-registry
 $preferences = json_encode($GLOBALS['egw_info']['user']['preferences']['common']);
 $ab_preferences = json_encode($GLOBALS['egw_info']['user']['preferences']['addressbook']);