Placeholder text is descriptive text displayed inside an input field until the field is filled. It disappears when you start typing in the field. Placeholder text is commonly used in current user interfaces so you have probably seen it before.
To set placeholder text in a field in your form, you only need to add a
placeholder option and a text value to the form-tag representing the field.
The placeholder text you set in the form tag is output into HTML as the value of the
placeholder attribute in the input field. For legacy browsers that don’t support HTML5’s
placeholder option is available on Contact Form 7 3.4 and higher. Users of older versions can still use
watermark instead of
placeholder. In Contact Form 7 3.4 and higher,
watermark is treated as an alias of
placeholder so you don’t need to change
placeholder when you update the plugin.