diff --git a/src/plugins/VerticalTabs/verticaltabsplugin.cpp b/src/plugins/VerticalTabs/verticaltabsplugin.cpp
--- a/src/plugins/VerticalTabs/verticaltabsplugin.cpp
+++ b/src/plugins/VerticalTabs/verticaltabsplugin.cpp
@@ -213,4 +213,5 @@
 
     m_styleSheet = QString::fromUtf8(file.readAll());
     emit styleSheetChanged(m_styleSheet);
+    file.close();
 }