Extend Ninja Forms' functionality by allowing textbox field to have unique values.
Ninja Forms is a great WordPress plugin and this plugin makes it even greater!
If you're using Ninja Forms for gathering data and one or more of textbox fields must be unique, this plugin is for you. The plugin is pretty straightforward to install, and has few settings only (language settings, basically).
Once installed, it will validate every submission to make sure the values for one or more fields are unique.
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