Magento 2.3.3 installation with composer fails: Could not delete

I’m trying to install Magento 2.3.3 on Debian 9 over a virtual machine. I’m stuck during the magento installation process because of the magento-composer-installer plugin. I also did a manual installation using the following command from the magento devdocs, but I always get the same error: composer –no-ansi –no-interaction install –no-progress –prefer-dist –optimize-autoloader Loading composer…

How to observe event before saveShipping or saveBilling actions for address validation

The shipping and billing addresses in our shop are processed with leading and trailing spaces, which is causing problems with the shipping labels. To fix this I want to hook into the process before the saveShippingAction() and saveBillingAction() of the OnepageController are invoked. I tried using the <controller_action_predispatch_checkout_onepage_saveBilling> and <controller_action_predispatch_checkout_onepage_saveShipping> event but the observer I…