diff --git a/CHANGELOG.md b/CHANGELOG.md
index a8d6d3ef4..c6e4fbb73 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@
 1. [](#bugfix)
     * Regression: Fixed language fallback
     * Regression: Allow SVG avatar images for users
+    * Fixed error in `Session::getFlashObject()` if Flex Form is being used
     
 # v1.7.0-beta.7
 ## 08/30/2019
diff --git a/system/src/Grav/Common/Session.php b/system/src/Grav/Common/Session.php
index cd9b2c175..f913810b4 100644
--- a/system/src/Grav/Common/Session.php
+++ b/system/src/Grav/Common/Session.php
@@ -125,7 +125,7 @@ class Session extends \Grav\Framework\Session\Session
 
                 /** @var FormFlash $flash */
                 $flash = $form ? $form->getFlash() : null;
-                $object = $flash ? [$sessionField => $flash->getLegacyFiles()] : null;
+                $object = $flash && method_exists($flash, 'getLegacyFiles') ? [$sessionField => $flash->getLegacyFiles()] : null;
             }
         }