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How to change the text from save button to submit button on Public Web Form?

How to change the text from save button to submit button on Public Web Form ?

You can do that using CSS and HTML. Or can create custom button.

How to create custom button on Public Web Form ??

I got it;
frappe.web_form.add_button_to_header(" Check Button","",function () {

    //do Something

});

Thanks