--- a/js/src/gc/Marking.cpp
+++ b/js/src/gc/Marking.cpp
@@ -2442,17 +2442,16 @@ IsMarkedInternal(T* thingp)
     *thingp = DispatchTyped(IsMarkedFunctor<T>(), *thingp, &rv);
     return rv;
 }
 
 bool
 js::gc::IsAboutToBeFinalizedDuringSweep(TenuredCell& tenured)
 {
     MOZ_ASSERT(!IsInsideNursery(&tenured));
-    MOZ_ASSERT(!tenured.runtimeFromAnyThread()->isHeapMinorCollecting());
     MOZ_ASSERT(tenured.zoneFromAnyThread()->isGCSweeping());
     if (tenured.arena()->allocatedDuringIncremental)
         return false;
     return !tenured.isMarked();
 }
 
 template <typename T>
 static bool
@@ -2462,21 +2461,19 @@ IsAboutToBeFinalizedInternal(T** thingp)
     T* thing = *thingp;
     JSRuntime* rt = thing->runtimeFromAnyThread();
 
     /* Permanent atoms are never finalized by non-owning runtimes. */
     if (ThingIsPermanentAtomOrWellKnownSymbol(thing) && !TlsPerThreadData.get()->associatedWith(rt))
         return false;
 
     Nursery& nursery = rt->gc.nursery;
-    MOZ_ASSERT_IF(!rt->isHeapMinorCollecting(), !IsInsideNursery(thing));
-    if (rt->isHeapMinorCollecting()) {
-        if (IsInsideNursery(thing))
-            return !nursery.getForwardedPointer(reinterpret_cast<JSObject**>(thingp));
-        return false;
+    if (IsInsideNursery(thing)) {
+        MOZ_ASSERT(rt->isHeapMinorCollecting());
+        return !nursery.getForwardedPointer(reinterpret_cast<JSObject**>(thingp));
     }
 
     Zone* zone = thing->asTenured().zoneFromAnyThread();
     if (zone->isGCSweeping()) {
         return IsAboutToBeFinalizedDuringSweep(thing->asTenured());
     } else if (zone->isGCCompacting() && IsForwarded(thing)) {
         *thingp = Forwarded(thing);
         return false;