diff --git a/roles/calibre-web/tasks/main.yml b/roles/calibre-web/tasks/main.yml
index c266001b2..bc222e24c 100644
--- a/roles/calibre-web/tasks/main.yml
+++ b/roles/calibre-web/tasks/main.yml
@@ -9,6 +9,7 @@
   lineinfile:
     path: /etc/ImageMagick-6/policy.xml
     regexp: '<policy domain="coder" rights="none" pattern="PDF" />'
+    backrefs: yes
     line: '  <policy domain="coder" rights="read" pattern="PDF" />'
     state: present
   when: is_debuntu