diff --git a/core/modules/link/src/Plugin/migrate/process/FieldLink.php b/core/modules/link/src/Plugin/migrate/process/FieldLink.php
index 353a89c..978f4e9 100644
--- a/core/modules/link/src/Plugin/migrate/process/FieldLink.php
+++ b/core/modules/link/src/Plugin/migrate/process/FieldLink.php
@@ -70,78 +70,11 @@ protected function canonicalizeUri($uri) {
     }
     else {
       // List of unicode-encoded characters that were allowed in URLs,
-      // according to link module in Drupal 7.
+      // according to link module in Drupal 7. Every character between ¿
+      // and ÿ (except × × and ÷ ÷) with the addition of
+      // Œ, œ and Ÿ.
       // @see http://cgit.drupalcode.org/link/tree/link.module?h=7.x-1.5-beta2#n1382
-      $link_ichars = implode('', [
-        "¿", // ¿
-        "À", // À
-        "Á", // Á
-        "Â", // Â
-        "Ã", // Ã
-        "Ä", // Ä
-        "Å", // Å
-        "Æ", // Æ
-        "Ç", // Ç
-        "È", // È
-        "É", // É
-        "Ê", // Ê
-        "Ë", // Ë
-        "Ì", // Ì
-        "Í", // Í
-        "Î", // Î
-        "Ï", // Ï
-        "Ð", // Ð
-        "Ñ", // Ñ
-        "Ò", // Ò
-        "Ó", // Ó
-        "Ô", // Ô
-        "Õ", // Õ
-        "Ö", // Ö
-        // × ×
-        "Ø", // Ø
-        "Ù", // Ù
-        "Ú", // Ú
-        "Û", // Û
-        "Ü", // Ü
-        "Ý", // Ý
-        "Þ", // Þ
-        "ß", // ß
-        "à", // à
-        "á", // á
-        "â", // â
-        "ã", // ã
-        "ä", // ä
-        "å", // å
-        "æ", // æ
-        "ç", // ç
-        "è", // è
-        "é", // é
-        "ê", // ê
-        "ë", // ë
-        "ì", // ì
-        "í", // í
-        "î", // î
-        "ï", // ï
-        "ð", // ð
-        "ñ", // ñ
-        "ò", // ò
-        "ó", // ó
-        "ô", // ô
-        "õ", // õ
-        "ö", // ö
-        // ÷ ÷
-        "ø", // ø
-        "ù", // ù
-        "ú", // ú
-        "û", // û
-        "ü", // ü
-        "ý", // ý
-        "þ", // þ
-        "ÿ", // ÿ
-        "Œ", // Œ
-        "œ", // œ
-        "Ÿ", // Ÿ
-      ]);
+      $link_ichars = '¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýþÿŒœŸ';
 
       // Pattern specific to internal links.
       $internal_pattern = "/^(?:[a-z0-9" . $link_ichars . "_\-+\[\] ]+)";
diff --git a/core/modules/link/src/Plugin/migrate/process/d6/FieldLink.php b/core/modules/link/src/Plugin/migrate/process/d6/FieldLink.php
index 4c4af30..19c5e35 100644
--- a/core/modules/link/src/Plugin/migrate/process/d6/FieldLink.php
+++ b/core/modules/link/src/Plugin/migrate/process/d6/FieldLink.php
@@ -14,5 +14,4 @@
  * @deprecated in Drupal 8.4.x, to be removed before Drupal 9.0.x. Use
  * \Drupal\link\Plugin\migrate\process\FieldLink instead.
  */
-class FieldLink extends GeneralPurposeFieldLink { }
-
+class FieldLink extends GeneralPurposeFieldLink {}
diff --git a/core/modules/link/tests/src/Unit/Plugin/migrate/process/FieldLinkTest.php b/core/modules/link/tests/src/Unit/Plugin/migrate/process/FieldLinkTest.php
index 48d603a..f765f6a 100644
--- a/core/modules/link/tests/src/Unit/Plugin/migrate/process/FieldLinkTest.php
+++ b/core/modules/link/tests/src/Unit/Plugin/migrate/process/FieldLinkTest.php
@@ -70,6 +70,14 @@ public function canonicalizeUriDataProvider() {
         'http://www.ßÀÑÐ¥ƒå¢ë.com',
         'http://www.ßÀÑÐ¥ƒå¢ë.com',
       ],
+      'Absolute URL with non-standard characters, without protocol prefix' => [
+        'www.ÐØÑ¢åþë.com',
+        'http://www.ÐØÑ¢åþë.com',
+      ],
+      'Absolute URL with non-standard top level domain' => [
+        'http://www.example.xxx',
+        'http://www.example.xxx',
+      ],
       'Internal link with fragment' => [
         '/node/10#top',
         'internal:/node/10#top',