更新：看起来这将在5.0以上版本中得到支持。参见票证#43458

默认设置是这样的(.ico) 文件显示在媒体网格视图中：

这是微模板的相应部分：

<# } else if ( \'image\' === data.type && data.sizes ) { #>
    <div class="centered">
        <img src="{{ data.size.url }}" draggable="false" alt="" />
    </div>
<# } else { #>
    <div class="centered"> 
        <# if ( data.image && data.image.src && data.image.src !== data.icon ) { #>
           <img src="{{ data.image.src }}" class="thumbnail" draggable="false" />
        <# } else { #>
            <img src="{{ data.icon }}" class="icon" draggable="false" />
        <# } #>
    </div>
    <div class="filename">
        <div>{{ data.filename }}</div>
    </div>
<# } #>

在哪里data.sizes 对于favicons为空。

方法1）使用wp_mime_type_icon 筛选器favicons的mime类型为image/x-icon.

我设法显示.ico 媒体网格中的文件可以通过以下方式查看：

add_filter( \'wp_mime_type_icon\', function( $icon, $mime, $post_id )
{
    if( $src = false || \'image/x-icon\' === $mime && $post_id > 0 )
        $src = wp_get_attachment_image_src( $post_id );

    return is_array( $src ) ? array_shift( $src ) : $icon;
}, 10, 3 ); 

这里的第三个参数wp_get_attachment_image_src 像$icon = false （默认情况下）以避免无限循环！

然后，图标显示如下：

方法2）使用wp_prepare_attachment_for_js 筛选加载媒体网格视图时，调用wp_ajax_query_attachments 处理程序。它执行以下附件查询：

$query = new WP_Query( $query );
$posts = array_map( \'wp_prepare_attachment_for_js\', $query->posts );

在这个wp_prepare_attachment_for_js 函数，将各种信息添加到WP_Post 并使用以下内容过滤帖子：

return apply_filters( \'wp_prepare_attachment_for_js\', $response, $attachment, $meta );

其中输出为$response 大堆

我们可以使用此筛选器添加favicons缺少的大小：

add_filter( \'wp_prepare_attachment_for_js\', function( $response, $attachment, $meta )
{
    if( \'image/x-icon\' === $response[\'mime\'] 
         && isset( $response[\'url\'] )
         && ! isset( $response[\'sizes\'][\'full\'] )
    )
    {
            $response[\'sizes\'] = array( \'full\' => array( \'url\' => $response[\'url\'] ) );
    }   
   return $response;
}, 10, 3 );

然后他们会这样出现：

请注意，我们只设置url 部分而非width, height 和orientation. 我们可以在wp_get_attachment_image_src() 例如，函数。但我让你来决定；-）

一些$response 示例：

Array 
(
    [id] => 803
    [title] => favicon
    [filename] => favicon.ico
    [url] => http://example.tld/wp-content/uploads/2015/02/favicon.ico
    [link] => http://example.tld/?attachment_id=803
    [alt] => 
    [author] => 11
    [description] => 
    [caption] => 
    [name] => favicon
    [status] => inherit
    [uploadedTo] => 0
    [date] => 1423791136000
    [modified] => 1423791136000
    [menuOrder] => 0
    [mime] => image/x-icon
    [type] => image
    [subtype] => x-icon
    [icon] => http://example.tld/wp-includes/images/media/default.png
    [dateFormatted] => February 13, 2015
    [nonces] => Array
        (
            [update] => 4fac983f49
            [delete] => efd563466d
            [edit] => df266bf556
        )

    [editLink] => http://example.tld/wp-admin/post.php?post=803&action=edit
    [meta] => 
    [authorName] => someuser
    [filesizeInBytes] => 1406
    [filesizeHumanReadable] => 1 kB
    [compat] => Array
        (
            [item] => 
            [meta] => 
        )

)

Array
(
    [id] => 733
    [title] => WordPress-Logo
    [filename] => WordPress-Logo.jpg
    [url] => http://example.tld/wp-content/uploads/2015/02/WordPress-Logo.jpg
    [link] => http://example.tld/2015/02/10/test/wordpress-logo/
    [alt] => 
    [author] => 1
    [description] =>
    [caption] =>
    [name] =>  wordpress-logo
    [status] => inherit
    [uploadedTo] => 784
    [date] => 1423314735000
    [modified] => 1423571320000
    [menuOrder] => 0
    [mime] => image/jpeg
    [type] => image
    [subtype] => jpeg
    [icon] => http://example.tld/wp-includes/images/media/default.png
    [dateFormatted] => February 7, 2015
    [nonces] => Array
        (
            [update] => cb6a4bca10
            [delete] => 068a4d3897
            [edit] => 14b7d201ff
        )

    [editLink] => http://example.tld/wp-admin/post.php?post=733&action=edit
    [meta] => 
    [authorName] => someuser
    [uploadedToLink] => http://example.tld/wp-admin/post.php?post=784&action=edit
    [uploadedToTitle] => 20150209021847
    [filesizeInBytes] => 127668
    [filesizeHumanReadable] => 125 kB
    [sizes] => Array
        (
            [thumbnail] => Array
                (
                    [height] => 150
                    [width] => 150
                    [url] => http://example.tld/wp-content/uploads/2015/02/WordPress-Logo-150x150.jpg
                    [orientation] => landscape
                )

            [medium] => Array
                (
                    [height] => 184
                    [width] => 300
                    [url] => http://example.tld/wp-content/uploads/2015/02/WordPress-Logo-300x184.jpg
                    [orientation] => landscape
                )

            [full] => Array
                (
                    [url] => http://example.tld/wp-content/uploads/2015/02/WordPress-Logo.jpg
                    [height] => 620
                    [width] => 1010
                    [orientation] => landscape
                )

        )

    [height] => 620
    [width] => 1010
    [orientation] => landscape
    [compat] => Array
        (
            [item] => 
            [meta] => 
        )

)