diff --git a/vcl/unx/gtk3_kde5/gtk3_kde5_folderpicker.cxx b/vcl/unx/gtk3_kde5/gtk3_kde5_folderpicker.cxx
index ad89374b47c77ecd3a08ffcdb00e5e66c2a73e3e..fcfe9f51d685e81613e6ee9af056e1cf73ff5865 100644
--- a/vcl/unx/gtk3_kde5/gtk3_kde5_folderpicker.cxx
+++ b/vcl/unx/gtk3_kde5/gtk3_kde5_folderpicker.cxx
@@ -76,7 +76,11 @@ void SAL_CALL Gtk3KDE5FolderPicker::setTitle(const OUString& aTitle)
     m_ipc.sendCommand(Commands::SetTitle, aTitle);
 }
 
-sal_Int16 SAL_CALL Gtk3KDE5FolderPicker::execute() { return m_ipc.execute(); }
+sal_Int16 SAL_CALL Gtk3KDE5FolderPicker::execute()
+{
+    SolarMutexGuard g;
+    return m_ipc.execute();
+}
 
 // XCancellable