Hi @jwoo Welcome!
ERR_INVALID_HTTP_TOKEN means an HTTP header name is invalid, usually a stray space, a colon, or an invisible pasted character in the name. The Content-Type name in your node is fine, so it is coming from the Firecrawl “Header Auth account” credential, most likely the full “Authorization: Bearer fc-…” string pasted into the Name field, where the colon breaks it.
Firecrawl authenticates with a bearer token, so the clean fix is to drop the header credential. In the scrape_url node, set Generic Auth Type to Bearer Auth and select a Bearer credential holding only the raw key fc-.... n8n builds the Authorization: Bearer header itself, so there is no header name left to get wrong.
One more bug in the same node: the Content-Type header value is application/json {{ $json.url }}. Set it to plain application/json, or delete the header since n8n adds it automatically when the body is JSON.
Firecrawl auth and headers:
Personally, I would suggest using the Firecrawl node, I use it and it works perfectly.