diff --git a/nix-os/xdg-default-apps.nix b/nix-os/xdg-default-apps.nix
index 2211375..7412f27 100644
--- a/nix-os/xdg-default-apps.nix
+++ b/nix-os/xdg-default-apps.nix
@@ -8,6 +8,7 @@
     "application/xhtml+xml" = "vivaldi-stable.desktop";
     "text/html" = "vivaldi-stable.desktop";
     "x-scheme-handler/https" = "vivaldi-stable.desktop";
+    "application/pdf" = "vivaldi-stable.desktop";
 
     # Audio
     "audio/aiff" = "mpv.desktop";