Facebook’s link-preview crawler (facebookexternalhit) returns 403 on
the apex domain https://wellow.fyi, while every other social
crawler I’ve tested (Twitterbot, Slackbot, LinkedInBot, Discordbot,
WhatsApp) returns 200 from the same host with the same path. From
my own IP using curl -A "facebookexternalhit/1.1" I also get 200,
which means the 403 only fires for traffic actually coming from
Meta’s crawler IP range — pointing at edge-side IP-level treatment
that I have no project-level setting to control.
This is breaking Instagram DM and Facebook link previews for the
site. I’ve already gone through the obvious checklist and ruled
everything out (details below) — appears to be something Meta-IP-
specific at Vercel’s edge.
Current:
- Facebook Sharing Debugger reports “Bad Response Code: 403” on
https://wellow.fyi (and on cache-busted variants like
Wellow · Invest from your worldview) - Debugger UI suggests “could be due to a robots.txt block” — but
robots.txt is permissive (see below) so that’s a misleading hint - All other social crawler user agents return 200 from the same URL
Expected:
- facebookexternalhit gets 200 with our OG metadata, same as every
other crawler. Instagram/Facebook link previews populate.
Project name: wellow-research
Production URL: https://wellow.fyi
Framework: Next.js 16 (App Router, Turbopack)
Plan: Hobby
Region: iad1 (US East)
Deployment: latest commit on main
DNS: apex A → 216.198.79.1, www → CNAME to vercel-dns
(managed via GoDaddy)
Reproduction URL for FB debugger:
https://developers.facebook.com/tools/debug/?q=https%3A%2F%2Fwellow.fyi