diff --git a/src/Mod/Plot/Plot.py b/src/Mod/Plot/Plot.py
index 78e117439c..a57d501814 100644
--- a/src/Mod/Plot/Plot.py
+++ b/src/Mod/Plot/Plot.py
@@ -30,7 +30,13 @@ try:
     import matplotlib
     matplotlib.use('Qt5Agg')
 
-    import matplotlib.pyplot as plt
+    # Force matplotlib to use PySide backend by temporarily unloading PyQt
+    if 'PyQt5.QtCore' in sys.modules:
+        del sys.modules['PyQt5.QtCore']
+        import matplotlib.pyplot as plt
+        import PyQt5.QtCore
+    else:
+        import matplotlib.pyplot as plt
 
     from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
     from matplotlib.backends.backend_qt5agg import NavigationToolbar2QT as NavigationToolbar