Mozilla says the following about HTTP 103 Early Hints: > Note: For compatibility reasons it is recommended to only send HTTP 103 Early Hints responses over HTT

Mozilla says the following about HTTP 103 Early Hints: > Note: For compatibility reasons it is recommended to only send HTTP 103 Early Hints responses over HTTP/2 or later, unless the client is known to handle informational responses correctly. > Most browsers limit support to HTTP/2 or later for this reason.