Feature: Support upcoming PHP 8 release, update to reactphp/socket v1.6 and adjust type checks for invalid chunk headers. (#391 by @clue)

Feature: Consistently resolve base URL according to HTTP specs. (#379 by @clue)

Feature / Fix: Expose Transfer-Encoding: chunked response header and fix chunked responses for HEAD requests. (#381 by @clue)

Internal refactoring to remove unneeded MessageFactory and Response classes. (#380 and #389 by @clue)

Minor documentation improvements and improve test suite, update to support PHPUnit 9.3. (#385 by @clue and #393 by @SimonFrings)