I need to populate name of current user in Custom DFF based upon the action of button.

Summary:

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I need to populate the name of user who click on "Complete" button on AR Invoice Page.

We have created DFF in order capture the value of current user who clicks on "COMPLETE" button. Could you please help if the requirement can be achieved from Sandbox and writing the code and defaulting the current user who clicks on "COMPLETE" button.

Note : This DFF would be read only DFF.

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