Merge branch '5.4' into 6.4

* 5.4:
  detect wrong e-mail validation modes
  read form values using the chain data accessor
  [Validator] Review Bulgarian (bg) translation
  Reviewed italian translation
  Fix french translation
  call substr() with integer offsets
  review: FR translation
  Update spanish and catalan translations
  Updated id=113 Arabic translation.
  #53771 Updated validator Lithuanian translations
  review: translation RU
  [PropertyInfo] Fix PHPStan properties type in trait
  [Validator] review validators.lv.xlf
  Review translation

Parser.php

@@ -638,12 +638,12 @@ private function getNextEmbedBlock(?int $indentation = null, bool $inSequence =
             }
 
             if ($this->isCurrentLineBlank()) {
-                $data[] = substr($this->currentLine, $newIndent);
+                $data[] = substr($this->currentLine, $newIndent ?? 0);
                 continue;
             }
 
             if ($indent >= $newIndent) {
-                $data[] = substr($this->currentLine, $newIndent);
+                $data[] = substr($this->currentLine, $newIndent ?? 0);
             } elseif ($this->isCurrentLineComment()) {
                 $data[] = $this->currentLine;
             } elseif (0 == $indent) {

Tests/ParserTest.php

@@ -1478,13 +1478,13 @@ public static function getBinaryData()
 data: !!binary |
     SGVsbG8gd29ybGQ=
 EOT
-    ],
+            ],
             'containing spaces in block scalar' => [
                 <<<'EOT'
 data: !!binary |
     SGVs bG8gd 29ybGQ=
 EOT
-    ],
+            ],
         ];
     }
 
@@ -2971,6 +2971,11 @@ public function testParseIdeographicSpaces()
         ], $this->parser->parse($expected));
     }
 
+    public function testSkipBlankLines()
+    {
+        $this->assertSame(['foo' => [null]], (new Parser())->parse("foo:\n-\n\n"));
+    }
+
     private function assertSameData($expected, $actual)
     {
         $this->assertEquals($expected, $actual);