- BC Warning: To prevent abuse of our includeFile() function it is now gone, it was not part of the official API but may still cause issues if some code incorrectly relied on it (#11015)
- Improved version guessing of require command to use the dependency resolution result instead of using the latest available version (except if you run with --no-update) (#11160)
- Improved version selection in archive command (#11230)
- Added autocompletion of config option names in the config command (#11130)
- Added support for writing custom commands as Command classes (#11151)
- Added hard failure when installing from a lock file which does not satisfy the composer.json requirements (#11195)
- Added warning when the outdated command rejects a new package due to unmet platform requirements (#11113)
- Added support for bump command to bump >=x to >=installed-version (#11179)
- Added --download-only flag to install command to only download and prime the cache with the package archives (#11041)
- Added autoconfiguration of github-domains/gitlab-domains when GitHub/GitLab credentials are configured for a custom domain (#11062)
- Added hard failure (throw) if COMPOSER_AUTH is present and malformed JSON (#11085)
- Added interactive prompt to run-script and exec commands if run without any argument (#11157)
- Added interactive prompt where to store credentials when a project-local auth.json exists (#11188)
- Fixed full disk warning to be shown when less than 100MiB is available (#11190)
- Fixed cache keys to allow _ to avoid conflicts between package names like a-b and a_b (#11229)
- Fixed docker compatibility by making paths more portable even if the project is installed at / (#11169)
