Index: src/wp-content/themes/twentyseventeen/inc/icon-functions.php
===================================================================
--- src/wp-content/themes/twentyseventeen/inc/icon-functions.php	(revision 39163)
+++ src/wp-content/themes/twentyseventeen/inc/icon-functions.php	(working copy)
@@ -49,7 +49,6 @@
 		'icon'        => '',
 		'title'       => '',
 		'desc'        => '',
-		'aria_hidden' => true, // Hide from screen readers.
 		'fallback'    => false,
 	);
 
@@ -57,38 +56,53 @@
 	$args = wp_parse_args( $args, $defaults );
 
 	// Set aria hidden.
-	$aria_hidden = '';
+	$aria_hidden = ' aria-hidden="true"';
 
-	if ( true === $args['aria_hidden'] ) {
-		$aria_hidden = ' aria-hidden="true"';
-	}
-
 	// Set ARIA.
 	$aria_labelledby = '';
 
-	if ( $args['title'] && $args['desc'] ) {
-		$aria_labelledby = ' aria-labelledby="title desc"';
+	/*
+	 * Twenty Seventeen doesn't use the SVG title or description attributes; non-decorative icons are described with .screen-reader-text.
+	 *
+	 * However, child themes can use the title and description to add information to non-decorative SVG icons to improve accessibility.
+	 *
+	 * Example 1 with title: <?php echo twentyseventeen_get_svg( array( 'icon' => 'arrow-right', 'title' => __( 'This is the title', 'textdomain' ) ) ); ?>
+	 *
+	 * Example 2 with title and description: <?php echo twentyseventeen_get_svg( array( 'icon' => 'arrow-right', 'title' => __( 'This is the title', 'textdomain' ), 'desc' => __( 'This is the description', 'textdomain' ) ) ); ?>
+	 *
+	 * See https://www.paciellogroup.com/blog/2013/12/using-aria-enhance-svg-accessibility/.
+	 */
+	if ( $args['title'] ) {
+		$aria_hidden     = '';
+		$unique_id       = uniqid();
+		$aria_labelledby = ' aria-labelledby="title-' . $unique_id . '"';
+
+		if ( $args['desc'] ) {
+			$aria_labelledby = ' aria-labelledby="title-' . $unique_id . ' desc-' . $unique_id . '"';
+		}
 	}
 
 	// Begin SVG markup.
 	$svg = '<svg class="icon icon-' . esc_attr( $args['icon'] ) . '"' . $aria_hidden . $aria_labelledby . ' role="img">';
 
-	// If there is a title, display it.
+	// Display the title.
 	if ( $args['title'] ) {
-		$svg .= '<title>' . esc_html( $args['title'] ) . '</title>';
-	}
+		$svg .= '<title id="title-' . $unique_id . '">' . esc_html( $args['title'] ) . '</title>';
 
-	// If there is a description, display it.
-	if ( $args['desc'] ) {
-		$svg .= '<desc>' . esc_html( $args['desc'] ) . '</desc>';
+		// Display the desc only if the title is already set.
+		if ( $args['desc'] ) {
+			$svg .= '<desc id="desc-' . $unique_id . '">' . esc_html( $args['desc'] ) . '</desc>';
+		}
 	}
 
-	// Use absolute path in the Customizer so that icons show up in there.
-	if ( is_customize_preview() ) {
-		$svg .= '<use xlink:href="' . get_parent_theme_file_uri( '/assets/images/svg-icons.svg#icon-' . esc_html( $args['icon'] ) ) . '"></use>';
-	} else {
-		$svg .= '<use xlink:href="#icon-' . esc_html( $args['icon'] ) . '"></use>';
-	}
+	/*
+	 * Display the icon.
+	 *
+	 * The whitespace around `<use>` is intentional - it is a work around to a keyboard navigation bug in Safari 10.
+	 *
+	 * See https://core.trac.wordpress.org/ticket/38387.
+	 */
+	$svg .= ' <use xlink:href="#icon-' . esc_html( $args['icon'] ) . '"></use> ';
 
 	// Add some markup to use as a fallback for browsers that do not support SVGs.
 	if ( $args['fallback'] ) {