Hi Charaf,
This is supported! First, create a custom boolean variable and bind it to the "visible" property of the text or text entry field (attached image). The default value should be 'true'. Then, use a custom action to execute the data action, and then use a conditional to set the bound visibility variable to false if the field is null or empty string. The custom action can be assigned as the script's page load (initial) action.
https://help.mypurecloud.com/articles/define-custom-script-action/------------------------------
R. J. Smith
Genesys - Employees
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