diff --git a/config/files/usr/etc/chromium/policies/managed/hardening.json b/config/files/usr/etc/chromium/policies/managed/hardening.json
index 6863971..493c286 100644
--- a/config/files/usr/etc/chromium/policies/managed/hardening.json
+++ b/config/files/usr/etc/chromium/policies/managed/hardening.json
@@ -43,5 +43,6 @@
 	"ImportSavedPasswords": false,
 	"DefaultWebUsbGuardSetting": 2,
 	"DefaultWebBluetoothGuardSetting": 2,
-	"DefaultSerialGuardSetting": 2
+	"DefaultSerialGuardSetting": 2,
+	"AlwaysOpenPdfExternally": true
 }
\ No newline at end of file
diff --git a/config/files/usr/etc/chromium/policies/managed/hardening.json.readme.md b/config/files/usr/etc/chromium/policies/managed/hardening.json.readme.md
index cc82774..a903312 100644
--- a/config/files/usr/etc/chromium/policies/managed/hardening.json.readme.md
+++ b/config/files/usr/etc/chromium/policies/managed/hardening.json.readme.md
@@ -178,4 +178,8 @@
 
 **Disable serial port access by default**
 
-`"DefaultSerialGuardSetting": 2`
\ No newline at end of file
+`"DefaultSerialGuardSetting": 2`
+
+**Disable the internal PDF viewer**
+
+`"AlwaysOpenPdfExternally": true`
\ No newline at end of file