diff --git a/src/wp-includes/default-filters.php b/src/wp-includes/default-filters.php
index 2ae86d88f5..5f5464e03f 100644
--- a/src/wp-includes/default-filters.php
+++ b/src/wp-includes/default-filters.php
@@ -130,7 +130,7 @@ add_filter( 'the_title', 'convert_chars' );
 add_filter( 'the_title', 'trim'          );
 
 add_filter( 'the_content', 'wptexturize'                       );
-add_filter( 'the_content', 'convert_smilies'                   );
+add_filter( 'the_content', 'convert_smilies',               20 );
 add_filter( 'the_content', 'wpautop'                           );
 add_filter( 'the_content', 'shortcode_unautop'                 );
 add_filter( 'the_content', 'prepend_attachment'                );
diff --git a/tests/phpunit/tests/shortcode.php b/tests/phpunit/tests/shortcode.php
index 9f6a71d960..d28abf1ecd 100644
--- a/tests/phpunit/tests/shortcode.php
+++ b/tests/phpunit/tests/shortcode.php
@@ -4,7 +4,7 @@
  */
 class Tests_Shortcode extends WP_UnitTestCase {
 
-	protected $shortcodes = array( 'test-shortcode-tag', 'footag', 'bartag', 'baztag', 'dumptag', 'hyphen', 'hyphen-foo', 'hyphen-foo-bar', 'url' );
+	protected $shortcodes = array( 'test-shortcode-tag', 'footag', 'bartag', 'baztag', 'dumptag', 'hyphen', 'hyphen-foo', 'hyphen-foo-bar', 'url', 'img' );
 
 	function setUp() {
 		parent::setUp();
@@ -78,6 +78,16 @@ class Tests_Shortcode extends WP_UnitTestCase {
 		return 'http://www.wordpress.org/';
 	}
 
+	function _shortcode_img( $atts ) {
+		$out = '<img';
+		foreach ( $atts as $k => $v ) {
+			$out .= " $k=\"$v\"";
+		}
+		$out .= ' />';
+
+		return $out;
+	}
+
 	function test_noatts() {
 		do_shortcode('[test-shortcode-tag /]');
 		$this->assertEquals( '', $this->atts );
@@ -657,4 +667,13 @@ EOF;
 		$expected = "0 = =https://wordpress.org\n";
 		$this->assertEquals($expected, $out);
 	}
+
+	/**
+	 * @ticket 36306
+	 */
+	function test_smilies_arent_converted() {
+		$out = apply_filters( 'the_content', '[img alt="Hello :-) World"]' );
+		$expected = "<img alt=\"Hello :-) World\" />\n";
+		$this->assertEquals( $expected, $out );
+	}
 }