Applied this change on top of D25239. Afterwards, the "Create Blueprint" page on `/drydock/blueprint/edit/form/default/` after pressing the "Create Blueprint" button the page correctly renders the expected error that some fields cannot be empty.
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# src/infrastructure/customfield/standard/PhabricatorStandardCustomField.php
Also, try to create extra numeric fields (like in the User application) and try to send zero or 1 using Conduit `user.edit`.