# Remote MCP Connector: ~2 min hang then STREAM\_FAILED\_PLACEHOLDER\_ERROR + CORS failure on restricted-feature-loader chunk (Pro web, JP region, 2026-05-08)

**URL:** <https://community.perplexity.ai/t/remote-mcp-connector-2-min-hang-then-stream-failed-placeholder-error-cors-failure-on-restricted-feature-loader-chunk-pro-web-jp-region-2026-05-08/5106>\
**Category:** Bug Reports\
**Tags:** sonar-api\
**Created:** [May 10, 2026, 6:30pm UTC](https://community.perplexity.ai/t/remote-mcp-connector-2-min-hang-then-stream-failed-placeholder-error-cors-failure-on-restricted-feature-loader-chunk-pro-web-jp-region-2026-05-08/5106 "2026-05-10T18:30:38Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Juliusz\_Fedyk](https://sea1.discourse-cdn.com/flex001/user_avatar/community.perplexity.ai/juliusz_fedyk/32/3098_2.png) [@Juliusz\_Fedyk](https://community.perplexity.ai/u/Juliusz_Fedyk)\
**Post date:** [May 10, 2026, 6:30pm UTC](https://community.perplexity.ai/t/remote-mcp-connector-2-min-hang-then-stream-failed-placeholder-error-cors-failure-on-restricted-feature-loader-chunk-pro-web-jp-region-2026-05-08/5106/1 "2026-05-10T18:30:38Z")

</div>

**Platform:** Perplexity Pro, Desktop Web (Chrome), JP region  
**Date/Time:** 2026-05-08 ~14:15 JST  
**Connector:** mcp.workjournal.pro (remote MCP, OAuth-authenticated)

## What Happened

Prompting “try listing my journals from workjournal” triggered a tool call that hung for ~2 min 6 s, then collapsed to a red “Sorry, something went wrong” banner. Re-adding the connector multiple times did not help.

## Browser Console Errors

**1. CORS failure:** The `restricted-feature-loader` JS chunk (from `pplx-next-static-public.perplexity.ai`) was redirected through `perplexity-ai.cloudflareaccess.com`. The OPTIONS preflight returned no `Access-Control-Allow-Origin` header, so the script never loaded.

**2. Stream failure:** `PplxStreamError` type=`STREAM_FAILED_PLACEHOLDER_ERROR`, `errorCode=unknown`

## Request IDs

- Request ID: `f0d26f8e-958a-4efe-bd79-825b46bc21a9`
- Backend UUID: `22c0ef96-7f17-48f6-9081-6fb350879c90`

## MCP Server Verified Healthy (not the issue)

- discovery: 200 in 274ms
- unauthenticated POST: 401 in 486ms
- openid-config: 200 in 683ms
- JWKS: 200 in 203ms
- Same connector works on Grok, ChatGPT, Claude Desktop, and workjournal CLI

## Hypothesis

The `restricted-feature-loader` chunk is inadvertently gated behind Perplexity’s Cloudflare Access policy. Browsers never send cookies with OPTIONS preflights, so the chunk fails to load silently, breaking MCP stream rendering even when the backend responds successfully. After ~2 min the pplx-stream layer times out and shows the generic error. This aligns with a Warn-level Perplexity Website+API incident recorded by StatusGator on May 8, 2026.

## Research thread with full details

[https://www.perplexity.ai/search/when-you-read-this-from-a-work-pCxX.\_nyQfuMJ1Y7yA7o\_w](https://www.perplexity.ai/search/when-you-read-this-from-a-work-pCxX._nyQfuMJ1Y7yA7o_w)

---

<div class="post-metadata">

**Author:** ![Alex\_Romanov](https://sea1.discourse-cdn.com/flex001/user_avatar/community.perplexity.ai/alex_romanov/32/330_2.png) [@Alex\_Romanov](https://community.perplexity.ai/u/Alex_Romanov)\
**Post date:** [May 10, 2026, 6:37pm UTC](https://community.perplexity.ai/t/remote-mcp-connector-2-min-hang-then-stream-failed-placeholder-error-cors-failure-on-restricted-feature-loader-chunk-pro-web-jp-region-2026-05-08/5106/2 "2026-05-10T18:37:56Z")

</div>

Thanks for the thorough report, @Juliusz_Fedyk! Please make the thread ‘shareable’, too, so the team can look into this.