diff --git a/examples/tree_2d_dgsem/elixir_euler_kelvin_helmholtz_instability_sc_subcell.jl b/examples/tree_2d_dgsem/elixir_euler_kelvin_helmholtz_instability_sc_subcell.jl
index c9024d7f734..9e9fb45e7d1 100644
--- a/examples/tree_2d_dgsem/elixir_euler_kelvin_helmholtz_instability_sc_subcell.jl
+++ b/examples/tree_2d_dgsem/elixir_euler_kelvin_helmholtz_instability_sc_subcell.jl
@@ -85,6 +85,7 @@ callbacks = CallbackSet(summary_callback,
 
 stage_callbacks = (SubcellLimiterIDPCorrection(),
                    BoundsCheckCallback(save_errors = false, interval = 100))
+# `interval` is used when calling this elixir in the tests with `save_errors=true`.
 
 sol = Trixi.solve(ode, Trixi.SimpleSSPRK33(stage_callbacks = stage_callbacks);
                   dt = 1.0, # solve needs some value here but it will be overwritten by the stepsize_callback