diff --git a/src/plugins/debugger/debuggerengine.cpp b/src/plugins/debugger/debuggerengine.cpp
index 93bc013ae14..ff3bc707886 100644
--- a/src/plugins/debugger/debuggerengine.cpp
+++ b/src/plugins/debugger/debuggerengine.cpp
@@ -386,6 +386,10 @@ public:
         // This triggers activity in the EngineManager which
         // recognizes the rampdown by the m_perpective == nullptr above.
         perspective->destroy();
+
+        // disconnect the follow font size connection
+        TextEditorSettings::instance()->disconnect(this);
+
         delete perspective;
     }