diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 74f9d1df78..4742484ca4 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -865,6 +865,9 @@ list(APPEND SCADFILES_WITH_DIFFERENT_MANIFOLD_EXPECTATIONS
   # Different vertex order
   ${TEST_SCAD_DIR}/3mf/3mf-export.scad
   ${TEST_SCAD_DIR}/stl/stl-import-nonmanifold.scad
+
+  # Thin sliver of geometry which Manifold doesn't collapse
+  ${TEST_SCAD_DIR}/3D/issues/issue1165.scad 
 )
 
 list(APPEND SCADFILES_FAILING_WITH_MANIFOLD
diff --git a/tests/regression/manifold-cgalpng/issue1165-expected.png b/tests/regression/manifold-cgalpng/issue1165-expected.png
index e9164b65c7..9ec6eb3484 100644
Binary files a/tests/regression/manifold-cgalpng/issue1165-expected.png and b/tests/regression/manifold-cgalpng/issue1165-expected.png differ