--- a/scene.c
+++ b/scene.c
@@ -983 +983 @@
-void wlr_scene_tree_set_clip(struct wlr_scene_tree *tree, const struct wlr_box *clip) {
+bool wlr_scene_tree_set_clip(struct wlr_scene_tree *tree, const struct wlr_box *clip) {
@@ -989,2 +989,2 @@
-	if (!clip && !entry) return;
-	if (clip && entry && memcmp(&entry->box, clip, sizeof(*clip)) == 0) return;
+	if (!clip && !entry) return true;
+	if (clip && entry && memcmp(&entry->box, clip, sizeof(*clip)) == 0) return true;
@@ -1000 +1000,5 @@
-			abort();
+			// WHY: a mandatory clip must not fail open even if callers ignore false.
+			// CONTRACT: mask synchronously; caller owns future visibility admission.
+			// INVARIANT: never automatically re-enable an intentionally hidden tree.
+			wlr_scene_node_set_enabled(&tree->node, false);
+			return false;
@@ -1013,0 +1018 @@
+	return true;