diff --git a/tests/test_units.py b/tests/test_units.py
index 5b8a0ac65..853cec856 100644
--- a/tests/test_units.py
+++ b/tests/test_units.py
@@ -358,6 +358,7 @@ def test_to_agg_units(in_u, opfunc, op, exp, exp_u):
         attrs={"units": in_u},
     )
 
+    # FIXME: This is emitting warnings from deprecated DataArray.argmax() usage.
     out = to_agg_units(getattr(da, opfunc)(), da, op)
     np.testing.assert_allclose(out, exp)