There is no preview if the response content-type header is formatted with quotes around the charset: text/html; charset=”utf-8” instead of the usual text/html; charset=utf-8 .
Create a new HTTP GET request.
Preferrably set the User-Agent string to be a real browser’s.
Do a request against https://www.facebook.com/marketplace/
Observe the message:

Please authenticate to join the conversation.
Released
Feedback
Bug
Over 1 year ago

Endrik Einberg
Get notified by email when there are changes.
Released
Feedback
Bug
Over 1 year ago

Endrik Einberg
Get notified by email when there are changes.