diff --git a/core/modules/color/color.module b/core/modules/color/color.module
index 8bbb035..97fb835 100644
--- a/core/modules/color/color.module
+++ b/core/modules/color/color.module
@@ -619,13 +619,13 @@ function _color_render_images($theme, &$info, &$paths, $palette) {
   imagedestroy($source);
 
   // Cut out slices.
-  foreach ($info['slices'] as $file => $coord) {
-    list($x, $y, $width, $height) = $coord;
-    $base = drupal_basename($file);
+  foreach ($info['slices'] as $slice_info) {
+    list($x, $y, $width, $height) = $slice_info['coord'];
+    $base = drupal_basename($slice_info['file']);
     $image = drupal_realpath($paths['target'] . $base);
 
     // Cut out slice.
-    if ($file == 'screenshot.png') {
+    if ($slice_info['file'] == 'screenshot.png') {
       $slice = imagecreatetruecolor(150, 90);
       imagecopyresampled($slice, $target, 0, 0, $x, $y, 150, 90, $width, $height);
       \Drupal::configFactory()->getEditable('color.theme.' . $theme)
@@ -646,7 +646,7 @@ function _color_render_images($theme, &$info, &$paths, $palette) {
     drupal_chmod($image);
 
     // Build before/after map of image paths.
-    $paths['map'][$file] = $base;
+    $paths['map'][$slice_info['file']] = $base;
   }
 
   // Clean up target buffer.