diff --git a/crates/redact/src/interp.rs b/crates/redact/src/interp.rs
index 8ab7602503..edebb99dcb 100644
--- a/crates/redact/src/interp.rs
+++ b/crates/redact/src/interp.rs
@@ -884,6 +884,8 @@ fn xobject(
                     out.error = Some(error);
                     return None;
                 }
+                // No page: annotation appearances draw through a page's resources, never through a
+                // form's. The form's own patterns and soft masks are still counted.
                 if let Err(error) = crate::type3::prune_type3_from_resources(doc, &mut cleaned_res, content, None) {
                     out.error = Some(error);
                     return None;