| A | ↛ | JsonException removed |
| ⇢ | A | Request::setUri() added | |
| ⇢ | A | Message::__construct() added | |
| ⇢ | A | Request::__construct() added | |
| ⇢ | A | Message::addHeader() added | |
| ⇢ | A | Request::setRequestTarget() added | |
| ⇢ | A | Request::setMethod() added | |
| ⇢ | A | Response::setStatus() added | |
| ⇢ | A | Response::__construct() added | |
| ⇢ | A | Message::setProtocolVersion() added | |
| A | ↛ | Message::withHeaderObject() removed | |
| A | ↛ | Message::normalizeHeaderValue() removed | |
| A | ↛ | Message::withMultipleHeaders() removed | |
| A | ↛ | JsonException::assert() removed | |
| A | ↛ | Message::withHeaderCollection() removed |