No error displayed while there are failures

[esynaps]

The plugin does not work for me, all packages are failures and no error is displayed.

$ composer install --profile --prefer-dist --verbose -vvv
Reading ./composer.json
Loading config file C:/Users/GCC-MED/AppData/Roaming/Composer/config.json
Loading config file C:/Users/GCC-MED/AppData/Roaming/Composer/auth.json
Loading config file ./composer.json
Checked CA file C:\Users\GCC-MED\AppData\Local\Temp\opeD750.tmp: valid
Executing command (C:\www\esynaps\laravel1): git branch --no-color --no-abbrev -v
Executing command (C:\www\esynaps\laravel1): git describe --exact-match --tags
Executing command (C:\www\esynaps\laravel1): git log --pretty="%H" -n1 HEAD
Executing command (C:\www\esynaps\laravel1): hg branch
Executing command (C:\www\esynaps\laravel1): fossil branch list
Executing command (C:\www\esynaps\laravel1): fossil tag list
Executing command (C:\www\esynaps\laravel1): svn info --xml
Reading C:/Users/GCC-MED/AppData/Roaming/Composer/composer.json
Loading config file C:/Users/GCC-MED/AppData/Roaming/Composer/config.json
Loading config file C:/Users/GCC-MED/AppData/Roaming/Composer/auth.json
Loading config file C:/Users/GCC-MED/AppData/Roaming/Composer/composer.json
Loading config file C:\Users\GCC-MED\AppData\Roaming\Composer/auth.json
Reading C:\Users\GCC-MED\AppData\Roaming\Composer/auth.json
Reading C:\www\esynaps\laravel1/vendor/composer/installed.json
Reading C:/Users/GCC-MED/AppData/Roaming/Composer/vendor/composer/installed.json
Loading plugin gossi\composer\localdev\ComposerLocaldevPlugin
Loading plugin Hirak\Prestissimo\Plugin
Downloading https://repo.packagist.org/packages.json
Writing C:/Users/GCC-MED/AppData/Local/Composer/repo/https---repo.packagist.org/packages.json into cache
======= Here ========
Finished: success: 0, skipped: 0, failure: 4, total: 4
====================
Loading plugin Symfony\Thanks\Thanks
Running 1.7.2 (2018-08-16 16:57:12) with PHP 7.1.7 on Windows NT / 10.0

After debugging prestissimo/src/CurlMulti.php:142, I could have the error
SSL certificate problem: unable to get local issuer certificate

Would it be possible to display this kind of error in the console?

I think that $io->writeError does not work as expected in prestissimo/src/Prefetcher.php