- Add
autocomplete="off"
onto<form>
element; - Add hidden
<input>
withautocomplete="false"
as a first children element of the form.
<form autocomplete="off" method="post" action="">
<input autocomplete="false" name="hidden" type="text" style="display:none;">
...
This formation is going to prevent Chrome and Firefox to offer autofill and autocomplete for all input fields inside the form.