If you have an error like this, when you use a custom views filter plugin, the resent is now you need to have a config schema for all Views filter plugins.

The error :

Generate a random key.

$random_key = str_shuffle('abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'); // 62 characters
$random_key = substr($random_key, 0, 10); // 10 characters

Cherry pick

Example:

CAUTION : At this day (2017-10-12), Drupal commerce is very young. Therefor you can start the development of your e-commerce site but you may have bugs and security issues.