Fix #5290

src/guiengine/event_handler.cpp

@@ -482,9 +482,10 @@ void EventHandler::navigate(const NavigationDirection nav, const int playerID)
             assert(ribbon != NULL);
             if (ribbon->getRibbonType() == GUIEngine::RibbonType::RIBBON_VERTICAL_TABS)
             {
-                int new_selection = (nav == NAV_UP) ?
-                                   ribbon->getActiveChildrenNumber(playerID) - 1 : 0;
-                ribbon->setSelection(new_selection, playerID);
+                // Some of the tabs may be disabled. So we navigate until an active tab is found
+                (nav == NAV_UP) ? ribbon->setLastSelection(playerID)
+                                : ribbon->setFirstSelection(playerID);
+
                 // The tab selection triggers an action
                 sendEventToUser(ribbon, ribbon->m_properties[PROP_ID], playerID);
             }

src/guiengine/widgets/ribbon_widget.cpp

@@ -307,6 +307,30 @@ void RibbonWidget::removeChildNamed(const char* name)
     }
 }
 
+// ----------------------------------------------------------------------------
+
+ /** Sets the first active item within the ribbon as selected,
+  * or the last one if 'reverse_order' is true. */
+void RibbonWidget::setFirstSelection(const int playerID, bool reverse_order)
+{
+    // Despite the name, "active children" includes elements that have been created
+    // and disabled with setActive(false)
+    // TODO: rename it to be clearer
+    int id = (reverse_order) ? getActiveChildrenNumber(playerID) - 1 : 0;
+    while (id >= 0 && id <= (getActiveChildrenNumber(playerID) - 1))
+    {
+        if (m_active_children[id].isActivated())
+            break;
+
+        id = (reverse_order) ? id - 1 : id + 1;
+    }
+
+    // If every single element within the ribbon is desactivated, we will pick
+    // the last (first) even if disabled, but this case should not arise.
+    m_selection[playerID] = id;
+    updateSelection();
+}   // setFirstSelection
+
 // ----------------------------------------------------------------------------
 
 void RibbonWidget::select(std::string item, const int mousePlayerID)

src/guiengine/widgets/ribbon_widget.hpp

@@ -173,6 +173,13 @@ namespace GUIEngine
         /** Sets the ID of the selected item within the ribbon */
         void setSelection(const int i, const int playerID)
                              { m_selection[playerID] = i; updateSelection(); }
+
+        /** Sets the first active item within the ribbon as selected */
+        void setFirstSelection(const int playerID, bool reverse_order = false);
+
+        /** Sets the last active item within the ribbon as selected */
+        void setLastSelection(const int playerID)
+                             { setFirstSelection(playerID, true); }
 
         /** Select an item in the ribbon by its internal name */
         void select(std::string item, const int playerID);