I love Matomo and how it complies to GDPR for my visitors....
BUT: why would you track my server ip, url and installation details during your Version checking?
in /plugins/CoreUpdater/ReleaseChannel.php you add these params:
'piwik_version' => Version::VERSION,
'php_version' => PHP_VERSION,
'mysql_version' => Db::get()->getServerVersion(),
'release_channel' => $this->getId(),
'url' => Url::getCurrentUrlWithoutQueryString(),
'trigger' => Common::getRequestVar('module', '', 'string'),
'timezone' => API::getInstance()->getDefaultTimezone()
Now I get why you would like to track that info to get to know your user-base... I would like to know more about my visitors too, but I just cannot do that without their consent.
In my humble opinion, it would be better to have the options (apart from maybe piwik_version) optional and only added when the installer asks for consent and the admin/installer/maintainer agrees.