diff --git a/asset/js/zotero-import.js b/asset/js/zotero-import.js
index 907db36..0bf4ef9 100644
--- a/asset/js/zotero-import.js
+++ b/asset/js/zotero-import.js
@@ -1,4 +1,4 @@
-// Kept for compatibility with Omeka < 1.2.
+// Kept as long as pull request #1260 is not passed.
 Omeka.zoteroImportManageSelectedActions = function() {
     var selectedOptions = $('[value="update-selected"], [value="delete-selected"], #batch-form .batch-inputs .batch-selected');
     if ($('.batch-edit td input[type="checkbox"]:checked').length > 0) {
@@ -33,7 +33,7 @@ Omeka.zoteroImportManageSelectedActions = function() {
             $('<input type="hidden" name="resource_type">').val(resourceType)
         );
 
-        // Kept for compatibility with Omeka < 1.2.
+        // Kept as long as pull request #1260 is not passed.
         $('.select-all').change(function() {
             Omeka.zoteroImportManageSelectedActions();
         });
diff --git a/src/Controller/IndexController.php b/src/Controller/IndexController.php
index 519286a..03800da 100644
--- a/src/Controller/IndexController.php
+++ b/src/Controller/IndexController.php
@@ -124,7 +124,7 @@ public function exportAction()
         }
 
         // Set default values to simplify checks.
-        $params += array_fill_keys(['resource_type', 'resource_ids', 'query', 'batch_action', 'zotero_all'], null);
+        $params += array_fill_keys(['resource_type', 'resource_ids', 'query', 'batch_action'], null);
 
         $resourceType = $params['resource_type'];
         $resourceTypeMap = [
@@ -143,7 +143,9 @@ public function exportAction()
             ? (is_array($params['resource_ids']) ? $params['resource_ids'] : explode(',', $params['resource_ids']))
             : [];
         $params['resource_ids'] = $resourceIds;
-        $selectAll = $params['batch_action'] ? $params['batch_action'] === 'zotero-all' : (bool) $params['zotero_all'];
+        // Manage Omeka with or without pull request #1260 (with or without
+        // param batch_action), so check $resourceIds.
+        $selectAll = $params['batch_action'] ? $params['batch_action'] === 'zotero-all' : empty($resourceIds);
         $params['batch_action'] = $selectAll ? 'zotero-all' : 'zotero-selected';
 
         $query = null;