How to remove the size of an input? I create a very simple theme with "stable" parent theme. 

So far so good. 

The size of input is indicated in HTML, and it bothers me a lot for the layout of my forms. 

This is an example.

&lt;input (...) value="" size="60" maxlength="128"&gt;


I have of course looked in the stable theme, but in the template input.html.twig, it is only indicated &lt;input{{ attributes }} /&gt;{{ children }}.

I would like to remove the size indication to fully manage my layout in CSS. 

How can I achieve this?
This question is quite old but here a solution

/**
 * Implements template_preprocess_form_element().
 */
function mytheme_preprocess_input(&amp;$variables) {
  // remove size
  unset($variables['element']['#size'], $variables['element']['#attributes']['size'], $variables['attributes']['size']);
}