2.0.9 - released 2021-01-27

Changelog

Added warning if the curl extension is not enabled as it significantly degrades performance
Fixed InstalledVersions to report all packages when several vendor dirs are present in the same runtime
Fixed download speed when downloading large files
Fixed archive and path repo copies mishandling some .gitignore paths
Fixed root package classes not being available to the plugins/scripts during the initial install
Fixed cache writes to be atomic and better support multiple Composer processes running in parallel
Fixed preg jit issues when config or require modifies large composer.json files
Fixed compatibility with envs having open_basedir restrictions
Fixed exclude-from-classmap causing regex issues when having too many paths
Fixed compatibility issue with Symfony 4/5
Several small performance and debug output improvements