title: Safari autofill populates any field with a placeholder attribute containing the word "email" with the user's email address
body: <p>I found this bug recently which appears to affect the most recent version of Safari (10) on iOS 10.3.3. It may apply to previous versions or even the desktop version but this is the specific version I found the bug on.</p>
  
  <p>If you have a form <code>&lt;input&gt;</code> element with a <code>placeholder</code> attribute that contains the word <em>"email"</em> or <em>"e-mail"</em> (and maybe just <em>"mail"</em> - I didn't test that) then <strong>Safari will autofill that field with the user's email address</strong> even if the field should definitely not be an email address.</p>
  
  <p>I tested this with the following form field markup:</p>
  
  <pre><code>&lt;div class="field full-width"&gt;
      &lt;label class="required" for="MarketingSource" aria-required="true"&gt;What prompted you to get in touch with us today?&lt;/label&gt;
      &lt;input data-val="true" data-val-length="This field is limited to 255 characters" data-val-length-max="255" data-val-required="Please tell us how you heard about xxx" id="MarketingSource" name="MarketingSource" placeholder="E.g. recommended, Google, email, Sunday Times" type="text" value=""/&gt;    
  &lt;/div&gt;
  </code></pre>
  
  <p>As you can see, the only reference to anything about email is in the following markup:</p>
  
  <blockquote>
    <p>placeholder="E.g. recommended, Google, <strong>email</strong>, Sunday Times"</p>
  </blockquote>
  
  <p>You cannot turn off autocomplete on fields in any browser these days, so <code>autocomplete="off"</code> is a no-go.</p>
  
  <p>How can I get Safari to ignore this field instead of incorrectly autofilling it with an email address? It's messing up marketing attribution data in the back end.</p>