title: Rails, How to remove validates_attachment_content_type for Active Admin?
body: <p>I am using paperclip to allow users have their own avatar. I notice that when I go to active admin to either edit or create a new user I get an "avatar content type is invalid error" in the avatar content type field when that user does not have an avatar.</p>
  
  <p>I can overcome this error by typing in image/jpeg in the field but obviously this would not be ideal for other admin users to have to type that in every time they want to create or edit a user.</p>
  
  <p>User.rb</p>
  
  <pre><code>....   has_attached_file :avatar, :styles =&gt; { :medium =&gt; "300x300&gt;", :thumb =&gt; "100x100#" }, :default_url =&gt; "/images/:style/missing.png"
        validates_attachment_content_type :avatar, :content_type =&gt; /\Aimage\/.*\Z/....
  </code></pre>
  
  <p>Is there a way to keep validation but turn it off for active admin by hiding the field or some other method? Thanks. </p>