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Properties for validators are indexed with an incrementing number starting at zero for each object type. Note that if any custom validation is set up, it overrides the default check on that object type for extension matching alphanumeric, underscore, and dash.
Example error messages
Default error messages, when extension does not match alphanumeric, underscore, or dash. If you see these error messages in the UI or log output, consider modifying the default behavior by disabling the default checks, or setting custom validation (preferred).
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