diff --git a/libtaskmanager/xwindowtasksmodel.cpp b/libtaskmanager/xwindowtasksmodel.cpp
--- a/libtaskmanager/xwindowtasksmodel.cpp
+++ b/libtaskmanager/xwindowtasksmodel.cpp
@@ -471,6 +471,8 @@
     icon.addPixmap(KWindowSystem::icon(window, KIconLoader::SizeMedium, KIconLoader::SizeMedium, false));
     icon.addPixmap(KWindowSystem::icon(window, KIconLoader::SizeLarge, KIconLoader::SizeLarge, false));
 
+    appDataCache[window].icon = icon;
+
     return icon;
 }