diff --git a/mod/resource/type/file/resource.class.php b/mod/resource/type/file/resource.class.php
index a035ea699d4..8a27739b190 100644
--- a/mod/resource/type/file/resource.class.php
+++ b/mod/resource/type/file/resource.class.php
@@ -586,7 +586,11 @@ function set_encrypted_parameter() {
 }
 
 function setup_preprocessing(&$defaults){
-    if (!empty($defaults['popup'])) {
+
+    if (!isset($defaults['popup'])) {
+        // use form defaults
+
+    } else if (!empty($defaults['popup'])) {
         $defaults['windowpopup'] = 1;
         if (array_key_exists('popup', $defaults)) {
             $rawoptions = explode(',', $defaults['popup']);
diff --git a/mod/resource/type/html/resource.class.php b/mod/resource/type/html/resource.class.php
index c41e7b5b325..22678843c78 100644
--- a/mod/resource/type/html/resource.class.php
+++ b/mod/resource/type/html/resource.class.php
@@ -133,7 +133,11 @@ function display() {
 }
 
 function setup_preprocessing(&$defaults){
-    if (!empty($defaults['popup'])) {
+
+    if (!isset($defaults['popup'])) {
+        // use form defaults
+
+    } else if (!empty($defaults['popup'])) {
         $defaults['windowpopup'] = 1;
         if (array_key_exists('popup', $defaults)) {
             $rawoptions = explode(',', $defaults['popup']);
diff --git a/mod/resource/type/ims/resource.class.php b/mod/resource/type/ims/resource.class.php
index d063cd740c6..70cbff38c2a 100644
--- a/mod/resource/type/ims/resource.class.php
+++ b/mod/resource/type/ims/resource.class.php
@@ -608,7 +608,11 @@ class resource_ims extends resource_base {
 
 
     function setup_preprocessing(&$defaults){
-        if (!empty($defaults['popup'])) {
+
+        if (!isset($defaults['popup'])) {
+            // use form defaults
+    
+        } else if (!empty($defaults['popup'])) {
             $defaults['windowpopup'] = 1;
             if (array_key_exists('popup', $defaults)) {
                 $rawoptions = explode(',', $defaults['popup']);
diff --git a/mod/resource/type/repository/resource.class.php b/mod/resource/type/repository/resource.class.php
index 5b6de91b6bf..18bc1d3325a 100644
--- a/mod/resource/type/repository/resource.class.php
+++ b/mod/resource/type/repository/resource.class.php
@@ -512,7 +512,11 @@ function set_encrypted_parameter() {
 
 
 function setup_preprocessing(&$defaults){
-    if (!empty($defaults['popup'])) {
+
+    if (!isset($defaults['popup'])) {
+        // use form defaults
+
+    } else if (!empty($defaults['popup'])) {
         $defaults['windowpopup'] = 1;
         if (array_key_exists('popup', $defaults)) {
             $rawoptions = explode(',', $defaults['popup']);
diff --git a/mod/resource/type/text/resource.class.php b/mod/resource/type/text/resource.class.php
index 6c2af43e79d..426d1043644 100644
--- a/mod/resource/type/text/resource.class.php
+++ b/mod/resource/type/text/resource.class.php
@@ -132,7 +132,11 @@ function display() {
 
 
 function setup_preprocessing(&$defaults){
-    if (!empty($defaults['popup'])) {
+
+    if (!isset($defaults['popup'])) {
+        // use form defaults
+
+    } else if (!empty($defaults['popup'])) {
         $defaults['windowpopup'] = 1;
         if (array_key_exists('popup', $defaults)) {
             $rawoptions = explode(',', $defaults['popup']);