diff --git a/changelog.d/8461-register-dark-gc-tests.md b/changelog.d/8461-register-dark-gc-tests.md
new file mode 100644
index 0000000000..e0f48ad14f
--- /dev/null
+++ b/changelog.d/8461-register-dark-gc-tests.md
@@ -0,0 +1 @@
+Register `test_gap_gc_string_copy_source_rooting` and `test_gap_gc_string_repeat_reentrant_count` in `test-parity/gc_repsel_corpus.txt`. #8439 and #8443 added them to `test-files/` without registering them, so `scripts/gc_repsel_matrix.sh` never executed either — a GC regression test that never runs is not a gate. `check_test_registration` was red on `main`.
diff --git a/test-parity/gc_repsel_corpus.txt b/test-parity/gc_repsel_corpus.txt
index 0228a5a0ef..2f3805cd75 100644
--- a/test-parity/gc_repsel_corpus.txt
+++ b/test-parity/gc_repsel_corpus.txt
@@ -816,3 +816,11 @@ test_gap_gc_http2_pending_event_callback_rooting
 # `Object.getPrototypeOf(undefined)` throws. Pre-fix `bad > 0` under seeded
 # GC; post-fix `bad 0`. Clean under `PERRY_GEN_GC=0`.
 test_gap_gc_interp_global_this_rooting
+
+# #8439: `js_string_copy` borrowed its source's bytes across an allocation that
+# can trigger a moving minor. Registered so gc-stress / gc-moving-witnesses
+# actually execute it instead of leaving it dark on disk.
+test_gap_gc_string_copy_source_rooting
+# #8443: `String.prototype.repeat` held its receiver unrooted across a
+# re-entrant count coercion. Same reason.
+test_gap_gc_string_repeat_reentrant_count