diff --git a/src/dbp-official-signature-pdf-upload.js b/src/dbp-official-signature-pdf-upload.js
index 2da1fb50f63de9de386731ab2798354f502400b4..10f6a1fc730d732d62e61c5024e39965d8d633f4 100644
--- a/src/dbp-official-signature-pdf-upload.js
+++ b/src/dbp-official-signature-pdf-upload.js
@@ -563,6 +563,7 @@ class OfficialSignaturePdfUpload extends ScopedElementsMixin(DBPSignatureLitElem
                 /* Modal preview, upload and external auth */
                 div.right-container > * {
                     position: fixed;
+                    z-index: 1000;
                     padding: 10px;
                     top: 0;
                     left: 0;
diff --git a/src/dbp-qualified-signature-pdf-upload.js b/src/dbp-qualified-signature-pdf-upload.js
index f3bc4f800f67b246e7ca9e763c7820818cb64d85..f382da9e04c3dda087ad3653ea4152bf6090d938 100644
--- a/src/dbp-qualified-signature-pdf-upload.js
+++ b/src/dbp-qualified-signature-pdf-upload.js
@@ -704,6 +704,7 @@ class QualifiedSignaturePdfUpload extends ScopedElementsMixin(DBPSignatureLitEle
                 /* Modal preview, upload and external auth */
                 div.right-container > * {
                     position: fixed;
+                    z-index: 1000;
                     padding: 10px;
                     top: 0;
                     left: 0;
diff --git a/src/dbp-signature-verification-full.js b/src/dbp-signature-verification-full.js
index 65a2db7bceef0930deec1f085b0559dc27c0901f..bec0dc9f37fbaa098fd3a2171709b3b043cae6fe 100644
--- a/src/dbp-signature-verification-full.js
+++ b/src/dbp-signature-verification-full.js
@@ -515,6 +515,7 @@ class SignatureVerificationFull extends ScopedElementsMixin(DBPSignatureLitEleme
                 /* Modal preview, upload and external auth */
                 div.right-container > * {
                     position: fixed;
+                    z-index: 1000;
                     padding: 10px;
                     top: 0;
                     left: 0;