diff -r b0022324fb4e -r d2b58cf339fe QTfrontend/ui/widget/mapContainer.cpp
--- a/QTfrontend/ui/widget/mapContainer.cpp	Sun Mar 18 15:24:54 2018 +0100
+++ b/QTfrontend/ui/widget/mapContainer.cpp	Sun Mar 18 15:42:17 2018 +0100
@@ -541,7 +541,7 @@
     if(mdl.size())
         updateTheme(mdl.at(0));
     else
-        intSetIconlessTheme(theme);
+        setMissingTheme(theme);
 }
 
 void HWMapContainer::setRandomMap()
@@ -1197,13 +1197,18 @@
     }
 }
 
-void HWMapContainer::intSetIconlessTheme(const QString & name)
+void HWMapContainer::setMissingTheme(const QString & name)
 {
     if (name.isEmpty()) return;
 
     m_theme = name;
-    btnTheme->setIcon(QIcon());
+    QPixmap pixMissing = QPixmap(":/res/missingTheme@2x.png");
+    QIcon iconMissing  = QIcon();
+    iconMissing.addPixmap(pixMissing, QIcon::Normal);
+    iconMissing.addPixmap(pixMissing, QIcon::Disabled);
+    btnTheme->setIcon(iconMissing);
     btnTheme->setText(tr("Theme: %1").arg(name));
+    updateThemeButtonSize();
 }
 
 void HWMapContainer::setupMissionMapsView()