Bad value “false” for attribute “autocomplete” on element “form”.

The autocomplete attribute on a <form> element only accepts "on" or "off" as valid values — "false" is not a recognized keyword.

The autocomplete attribute controls whether the browser can automatically fill in form fields based on previously entered values. When set on a <form> element, it applies as the default behavior for all fields within that form. The valid values are "on" (the browser may auto-complete entries) and "off" (the browser should not auto-complete entries).

It's a common mistake to use "true" or "false" since many other attributes and programming languages use boolean-style values. However, the HTML specification explicitly defines only "on" and "off" for the <form> element's autocomplete attribute.

Note that individual <input> elements support a much wider range of autocomplete values (like "name", "email", "street-address", etc.), but these extended values do not apply to the <form> element itself.

Invalid Example

<form autocomplete="false" action="/submit" method="post">
  <label for="email">Email</label>
  <input type="email" id="email" name="email">
  <button type="submit">Submit</button>
</form>

Valid Example

<form autocomplete="off" action="/submit" method="post">
  <label for="email">Email</label>
  <input type="email" id="email" name="email">
  <button type="submit">Submit</button>
</form>

Learn more:

MDN Reference

HTML autocomplete attribute

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MDN Reference

The form element

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WHATWG Spec

Forms - WHATWG HTML Standard

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