diff --git a/config/configuration.sample.yml b/config/configuration.sample.yml
index 2036e9c8b7..b1adc6c91a 100644
--- a/config/configuration.sample.yml
+++ b/config/configuration.sample.yml
@@ -228,4 +228,6 @@ embed_bundle:
         - 1.5
         - 2
     audio_player: 'videojs'
-    audio_autoplay: false
\ No newline at end of file
+    audio_autoplay: false
+    document:
+        enable_pdfjs: true
\ No newline at end of file