diff --git a/src/lib/microcosm/feed.ts b/src/lib/microcosm/feed.ts
index c3f356d..88d714a 100644
--- a/src/lib/microcosm/feed.ts
+++ b/src/lib/microcosm/feed.ts
@@ -149,13 +149,23 @@ async function resolveFeedGenDid(
   return (rec?.value as {did?: string} | undefined)?.did
 }
 
+/**
+ * Feed generators we've seen reject a direct browser call (almost always a CORS
+ * block: the generator doesn't send Access-Control-Allow-Origin, so the browser
+ * refuses to read the response). We remember them to skip straight to the
+ * AppView next time instead of repeating a guaranteed-failing request. On native
+ * there is no CORS, so this set stays empty.
+ */
+const directFetchUnsupported = new Set<string>()
+
 /**
  * Fetch + hydrate one page of a custom (algorithmic) feed, with no AppView.
  *
- * Uses Slingshot's batch hydration: it proxies the feed generator's
- * getFeedSkeleton AND fetches every post record in ONE request, so we avoid N
- * per-post record fetches (which made feeds load one-by-one). Only author
- * identities are resolved afterward (cached + parallel).
+ * Calls the feed generator's getFeedSkeleton DIRECTLY (endpoint resolved via
+ * Slingshot), forwarding the viewer's service-auth token so personalized feeds
+ * work. The returned post uris are hydrated via Slingshot record reads. If the
+ * direct call can't be made (e.g. the generator lacks CORS headers in a
+ * browser), returns an empty page so the caller falls back to the AppView.
  */
 export async function buildCustomFeed(
   feedUri: string,
@@ -175,6 +185,9 @@ export async function buildCustomFeed(
   const feedGenDid = await resolveFeedGenDid(feedUri, signal)
   if (!feedGenDid) return {feed: []}
 
+  // Known to fail a direct browser call (CORS) - go straight to the AppView.
+  if (directFetchUnsupported.has(feedGenDid)) return {feed: []}
+
   const authorization = opts.getAuthorization
     ? await opts.getAuthorization(feedGenDid).catch(() => undefined)
     : undefined
@@ -182,6 +195,7 @@ export async function buildCustomFeed(
   // Call the feed generator's getFeedSkeleton DIRECTLY with the viewer's
   // service-auth token (no AppView, no Slingshot batch proxy). The generator
   // personalizes based on the token and returns an ordered list of post uris.
+  let corsBlocked = false
   const skeleton = await fetchFeedSkeletonDirect(
     {
       feedGenDid,
@@ -191,7 +205,13 @@ export async function buildCustomFeed(
       authorization,
     },
     signal,
-  ).catch(() => undefined)
+  ).catch((e: unknown) => {
+    // A browser CORS block surfaces as a TypeError ("Failed to fetch") with no
+    // status, distinct from an HTTP error. Remember it so we don't retry.
+    if (e instanceof TypeError) corsBlocked = true
+    return undefined
+  })
+  if (corsBlocked) directFetchUnsupported.add(feedGenDid)
   if (!skeleton || skeleton.order.length === 0) return {feed: []}
 
   // Hydrate each post uri into a PostView (records + authors via Slingshot,