diff --git a/pkgs/development/python-modules/plotpy/default.nix b/pkgs/development/python-modules/plotpy/default.nix
index 4ea7834f2a40..923ec62e533a 100644
--- a/pkgs/development/python-modules/plotpy/default.nix
+++ b/pkgs/development/python-modules/plotpy/default.nix
@@ -85,27 +85,32 @@ buildPythonPackage rec {
 
   passthru = {
     tests = {
-      # Upstream doesn't officially supports all of them, although they use
-      # qtpy, see: https://github.com/PlotPyStack/PlotPy/issues/20 . When this
-      # package was created, all worked besides withPySide2, with which there
-      # was a peculiar segmentation fault during the tests. In anycase, PySide2
-      # shouldn't be used for modern applications.
       withPyQt6 = plotpy.override {
         pyqt6 = pyqt6;
         qt6 = qt6;
       };
-      withPySide6 = plotpy.override {
-        pyqt6 = pyside6;
-        qt6 = qt6;
-      };
       withPyQt5 = plotpy.override {
         pyqt6 = pyqt5;
         qt6 = qt5;
       };
+    };
+    # Upstream doesn't officially supports all of them, although they use
+    # qtpy, see: https://github.com/PlotPyStack/PlotPy/issues/20
+    knownFailingTests = {
+      # Was failing with a peculiar segmentation fault during the tests, since
+      # this package was added to Nixpkgs. This is not too bad as PySide2
+      # shouldn't be used for modern applications.
       withPySide2 = plotpy.override {
         pyqt6 = pyside2;
         qt6 = qt5;
       };
+      # Has started failing too similarly to pyside2, ever since a certain
+      # version bump. See also:
+      # https://github.com/PlotPyStack/PlotPy/blob/v2.7.4/README.md?plain=1#L62
+      withPySide6 = plotpy.override {
+        pyqt6 = pyside6;
+        qt6 = qt6;
+      };
     };
   };