• Added active plugins to the diagnose command output (#12706)
• Fixed HTTP/3 causing issues with proxies (#12699)
• Fixed show command regression with long descriptions containing unicode characters (#12704)
• Fixed regression handling invalid unicode sequences in output (#12707)
• Fixed git rev-list usages to support older pre-2.33 git versions (#12705)
• Fixed issue handling paths with = in them on Windows (#12726)

Full Changelog: https://github.com/composer/composer/compare/2.9.3...2.9.4