diff --git a/invenio_app_rdm/config.py b/invenio_app_rdm/config.py
index d53731124..2e2c29b76 100644
--- a/invenio_app_rdm/config.py
+++ b/invenio_app_rdm/config.py
@@ -968,12 +968,12 @@ def github_link_render(record):
 
 PREVIEWER_PREFERENCE = [
     "csv_papaparsejs",
+    "pdfjs",
     "iiif_simple",
     "simple_image",
     "json_prismjs",
     "xml_prismjs",
     "mistune",
-    "pdfjs",
     "ipynb",
     "zip",
     "txt",
@@ -1001,12 +1001,14 @@ def github_link_render(record):
     "jp2": "jpeg2000",
     "jpeg": "jpeg",
     "jpg": "jpeg",
-    "pdf": "pdf",
     "png": "png",
     "tif": "tiff",
     "tiff": "tiff",
 }
 
+RECORDS_RESOURCES_IMAGE_FORMATS = ["." + ext for ext in IIIF_FORMATS.keys()]
+"""RECORDS_RESOURCES_IMAGE_FORMATS must contain all possible IIIF formats to ensure their metadata is extracted."""
+
 # Invenio-Pages
 # =============
 # See https://invenio-pages.readthedocs.io/en/latest/configuration.html