diff --git a/tests/auto/qgraphicswidget/qgraphicswidget.pro b/tests/auto/qgraphicswidget/qgraphicswidget.pro
index 533138c43b..64de1fc739 100644
--- a/tests/auto/qgraphicswidget/qgraphicswidget.pro
+++ b/tests/auto/qgraphicswidget/qgraphicswidget.pro
@@ -6,3 +6,4 @@ SOURCES  += tst_qgraphicswidget.cpp
 
 
 mac*:CONFIG+=insignificant_test
+qpa:contains(QT_CONFIG,xcb):CONFIG+=insignificant_test  # QTBUG-20778 unstable on qpa, xcb