I am following the guide to install plugins as per this page:
https://plugins.roundcube.net/
I did copy composer.json-dist on composer.json and added a plugin manually to this latter (not sure what I'm doing but here we go...)
Now when I go calling php composer.phar I get:
[Composer\Downloader\TransportException]
The "https://plugins.roundcube.net/packages.json" file could not be downloaded: Pe
er certificate CN=`roundcube.net' did not match expected CN=`plugins.roundcube.net
'
Failed to enable crypto
failed to open stream: operation failed
Not sure how to progress...
Thanks