1 files changed, 13 insertions, 0 deletions
diff --git a/src/extension/prefdialog/parameter-notebook.cpp b/src/extension/prefdialog/parameter-notebook.cpp
index a90935ca1..050c84f0d 100644
--- a/src/extension/prefdialog/parameter-notebook.cpp
+++ b/src/extension/prefdialog/parameter-notebook.cpp
@@ -15,6 +15,8 @@
 
 #include "parameter-notebook.h"
 
+#include <unordered_set>
+
 #include <gtkmm/box.h>
 #include <gtkmm/notebook.h>
 
@@ -133,6 +135,17 @@ ParamNotebook::ParamNotebook(Inkscape::XML::Node *xml, Inkscape::Extension::Exte
         g_warning("No (valid) pages for parameter '%s' in extension '%s'", _name, _extension->get_id());
     }
 
+    // check for duplicate page names
+    std::unordered_set<std::string> names;
+    for (auto child : _children) {
+        ParamNotebookPage *page = static_cast<ParamNotebookPage *>(child);
+        auto ret = names.emplace(page->_name);
+        if (!ret.second) {
+            g_warning("Duplicate page name ('%s') for parameter '%s' in extension '%s'.",
+                      page->_name, _name, _extension->get_id());
+        }
+    }
+
     // get value (initialize with value of first page if pref is empty)
     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
     _value = prefs->getString(pref_name());