diff --git a/invenio_previewer/templates/invenio_previewer/pdfjs.html b/invenio_previewer/templates/invenio_previewer/pdfjs.html
index b12646c2b71fa57d947295c28c9d70760718acbe..d65fa8188a5dfb49d2e80548a7be072329fd08cb 100644
--- a/invenio_previewer/templates/invenio_previewer/pdfjs.html
+++ b/invenio_previewer/templates/invenio_previewer/pdfjs.html
@@ -2,6 +2,7 @@
 
   This file is part of Invenio.
   Copyright (C) 2015-2019 CERN.
+  Copyright (C)      2022 TU Wien.
 
   Invenio is free software; you can redistribute it and/or modify it
   under the terms of the MIT License; see LICENSE file for more details.
@@ -10,7 +11,7 @@
 {%- extends config.PREVIEWER_BASE_TEMPLATE %}
 
 {%- block html_tags %}
-  {{ html_tags }}
+  {{ html_tags|safe }}
 {%- endblock %}
 
 {%- block head %}
diff --git a/invenio_previewer/templates/semantic-ui/invenio_previewer/pdfjs.html b/invenio_previewer/templates/semantic-ui/invenio_previewer/pdfjs.html
index 28b7445a197b3d4cf602e998f074b63a0f136cad..7dfda54bc1ba95c3c13a4d0d4a511473963661cf 100644
--- a/invenio_previewer/templates/semantic-ui/invenio_previewer/pdfjs.html
+++ b/invenio_previewer/templates/semantic-ui/invenio_previewer/pdfjs.html
@@ -2,6 +2,7 @@
 
   This file is part of Invenio.
   Copyright (C) 2015-2020 CERN.
+  Copyright (C)      2022 TU Wien.
 
   Invenio is free software; you can redistribute it and/or modify it
   under the terms of the MIT License; see LICENSE file for more details.
@@ -10,7 +11,7 @@
 {%- extends config.PREVIEWER_BASE_TEMPLATE %}
 
 {%- block html_tags %}
-  {{ html_tags }}
+  {{ html_tags|safe }}
 {%- endblock %}
 
 {%- block head %}