diff --git a/core/lib/Drupal/Core/StringTranslation/TranslationManager.php b/core/lib/Drupal/Core/StringTranslation/TranslationManager.php
index 89df04d..f455a9c 100644
--- a/core/lib/Drupal/Core/StringTranslation/TranslationManager.php
+++ b/core/lib/Drupal/Core/StringTranslation/TranslationManager.php
@@ -175,6 +175,10 @@ public function formatPluralTranslated($count, $translation, array $args = array
     $args['@count'] = $count;
     $translated_array = explode(LOCALE_PLURAL_DELIMITER, $translation);
 
+    if ($count == 1) {
+      return String::format($translated_array[0], $args);
+    }
+
     // Get the plural index through the gettext formula.
     // @todo implement static variable to minimize function_exists() usage.
     $index = (function_exists('locale_get_plural')) ? locale_get_plural($count, isset($options['langcode']) ? $options['langcode'] : NULL) : -1;
@@ -189,9 +193,9 @@ public function formatPluralTranslated($count, $translation, array $args = array
       }
       else {
         // If the index cannot be computed or there's no translation, use
-        // the most common rules of using the first item for 1 and the second
-        // item for all other numbers.
-        $return = $translated_array[(int)($count != 1)];
+        // the second plural form as a fallback (which allows for most flexibility
+        // with the replaceable @count value).
+        $return = $translated_array[1];
       }
     }
 
diff --git a/core/modules/config_translation/src/FormElement/FormElementBase.php b/core/modules/config_translation/src/FormElement/FormElementBase.php
index 19114ee..e13cc31 100644
--- a/core/modules/config_translation/src/FormElement/FormElementBase.php
+++ b/core/modules/config_translation/src/FormElement/FormElementBase.php
@@ -91,9 +91,7 @@ public function getTranslationBuild(LanguageInterface $source_language, Language
    *   A render array for the source value.
    */
   protected function getSourceElement(LanguageInterface $source_language, $source_config) {
-    // @todo Should be able to render source as singular+plurals. Similar
-    // to TranslateEditForm::buildForm(), but here the source may also be
-    // multi-plural.
+    // @todo Should support singular+plurals https://www.drupal.org/node/2454829
     if ($source_config) {
       $value = '<span lang="' . $source_language->getId() . '">' . nl2br($source_config) . '</span>';
     }
@@ -164,8 +162,7 @@ protected function getSourceElement(LanguageInterface $source_language, $source_
    */
   protected function getTranslationElement(LanguageInterface $translation_language, $source_config, $translation_config) {
     // Add basic properties that apply to all form elements.
-    // @todo Needs support for possibly singular+plurals input if the source
-    // was singular/plural. As in TranslateEditForm::buildForm().
+    // @todo Should support singular+plurals https://www.drupal.org/node/2454829
     return array(
       '#title' => $this->t('!label <span class="visually-hidden">(!source_language)</span>', array(
         '!label' => $this->t($this->definition['label']),
diff --git a/core/modules/views/src/Tests/Plugin/NumericFormatPluralTest.php b/core/modules/views/src/Tests/Plugin/NumericFormatPluralTest.php
index 705279a..a673ef4 100644
--- a/core/modules/views/src/Tests/Plugin/NumericFormatPluralTest.php
+++ b/core/modules/views/src/Tests/Plugin/NumericFormatPluralTest.php
@@ -92,7 +92,7 @@ function testNumericFormatPlural() {
     // Add Slovenian and set its plural formula to test multiple plural forms.
     $edit = ['predefined_langcode' => 'sl'];
     $this->drupalPostForm('admin/config/regional/language/add', $edit, t('Add language'));
-    $formula = 'nplurals=4; plural=(n%100==1 ? 1 : n%100==2 ? 2 : n%100==3 || n%100==4 ? 3 : 0);';
+    $formula = 'nplurals=4; plural=(n%100==1 ? 0 : n%100==2 ? 1 : n%100==3 || n%100==4 ? 2 : 3);';
     $header = new PoHeader();
     list($nplurals, $formula) = $header->parsePluralForms($formula);
     debug($formula);
@@ -123,12 +123,12 @@ function testNumericFormatPlural() {
 
     // The view should now use the new plural configuration.
     $this->drupalGet('sl/numeric-test');
-    $this->assertRaw('<span class="field-content">0 time0</span>');
-    $this->assertRaw('<span class="field-content">1 time1</span>');
-    $this->assertRaw('<span class="field-content">2 time2</span>');
-    $this->assertRaw('<span class="field-content">3 time3</span>');
-    $this->assertRaw('<span class="field-content">4 time3</span>');
-    $this->assertRaw('<span class="field-content">42 time0</span>');
+    $this->assertRaw('<span class="field-content">0 time3</span>');
+    $this->assertRaw('<span class="field-content">1 time0</span>');
+    $this->assertRaw('<span class="field-content">2 time1</span>');
+    $this->assertRaw('<span class="field-content">3 time2</span>');
+    $this->assertRaw('<span class="field-content">4 time2</span>');
+    $this->assertRaw('<span class="field-content">42 time3</span>');
   }
 
   /**