diff --git a/4dev/checking/phpunit.sh b/4dev/checking/phpunit.sh
index 50badb6f..931afd11 100755
--- a/4dev/checking/phpunit.sh
+++ b/4dev/checking/phpunit.sh
@@ -19,6 +19,7 @@ if [ ! -z "${1}" ]; then
 		# "8.0") php_bin="/usr/bin/php8.0 "; ;;
 		# "8.1") php_bin="/usr/bin/php8.1 "; ;;
 		"8.2") php_bin="/usr/bin/php8.2 "; ;;
+		"8.3") php_bin="/usr/bin/php8.4 "; ;;
 		*) echo "Not support PHP: ${1}"; exit; ;;
 	esac;
 fi;
@@ -29,6 +30,7 @@ if [ ! -z "${2}" ] && [ -z "${php_bin}" ]; then
 		# "8.0") php_bin="/usr/bin/php8.0 "; ;;
 		# "8.1") php_bin="/usr/bin/php8.1 "; ;;
 		"8.2") php_bin="/usr/bin/php8.2 "; ;;
+		"8.3") php_bin="/usr/bin/php8.3 "; ;;
 		*) echo "Not support PHP: ${1}"; exit; ;;
 	esac;
 fi;
diff --git a/4dev/tests/Convert/CoreLibsConvertMimeEncodeTest.php b/4dev/tests/Convert/CoreLibsConvertMimeEncodeTest.php
index 00b1055e..1c2c47c7 100644
--- a/4dev/tests/Convert/CoreLibsConvertMimeEncodeTest.php
+++ b/4dev/tests/Convert/CoreLibsConvertMimeEncodeTest.php
@@ -33,15 +33,14 @@ final class CoreLibsConvertMimeEncodeTest extends TestCase
 				'The quick brown fox jumps over the lazy sheep that sleeps in the ravine '
 					. 'and has no idea what is going on here',
 				'UTF-8',
-				'The quick brown fox jumps over the lazy sheep that sleeps in the ravine '
-					. 'and has no idea what is going on here'
+				"The quick brown fox jumps over the lazy sheep that sleeps in the ravine and\r\n"
+					. ' has no idea what is going on here'
 			],
 			'standard with special chars UTF-8' => [
 				'This is ümläßtと漢字もカタカナ！!^$%&',
 				'UTF-8',
-				'This is =?UTF-8?B?w7xtbMOkw59044Go5ryi5a2X44KC44Kr44K/44Kr44OK77yBIV4k?='
-					. "\r\n"
-					. ' =?UTF-8?B?JQ==?=&'
+				"This is =?UTF-8?B?w7xtbMOkw59044Go5ryi5a2X44KC44Kr44K/44Kr44OK77yBIV4k?=\r\n"
+					. ' =?UTF-8?B?JSY=?='
 			],
 			'35 chars and space at the end UTF-8' => [
 				'12345678901234567890123456789012345 '
@@ -62,9 +61,8 @@ final class CoreLibsConvertMimeEncodeTest extends TestCase
 					. 'is there a space?',
 				'UTF-8',
 				"=?UTF-8?B?44Kr44K/44Kr44OK44Kr44K/44Kr44OK44GL44Gq44Kr44K/44Kr44OK44Kr?=\r\n"
-					. " =?UTF-8?B?44K/44Kr44OK?=\r\n"
-					. " =?UTF-8?B?44GL44Gq44Kr44K/44Kr44OK44Kr44K/44Kr44OK44GL44Gq44Kr44K/44Kr?=\r\n"
-					. " =?UTF-8?B?44OK44Kr44K/?= is there a =?UTF-8?B?c3BhY2U/?="
+					. " =?UTF-8?B?44K/44Kr44OK44GL44Gq44Kr44K/44Kr44OK44Kr44K/44Kr44OK44GL44Gq?=\r\n"
+					. " =?UTF-8?B?44Kr44K/44Kr44OK44Kr44K/IGlzIHRoZXJlIGEgc3BhY2U/?="
 			]
 		];
 	}
@@ -85,16 +83,28 @@ final class CoreLibsConvertMimeEncodeTest extends TestCase
 		// print "MIME: -" . $encoded . "-\n";
 		$this->assertEquals(
 			$expected,
-			$encoded
+			$encoded,
+			"__mbMimeEncode"
 		);
 		$decoded = mb_decode_mimeheader($encoded);
-		// print "INPUT  : " . $input . "\n";
-		// print "DECODED: " . $decoded . "\n";
+		// print "ENCODED: " . $encoded . "\n";
+		// print "INPUT  : " . $input . " | " . mb_strlen($input) . "\n";
+		// print "DECODED: " . $decoded . " | " . mb_strlen($decoded) . "\n";
+		// $test_enc = mb_encode_mimeheader($input, $encoding);
+		// $test_dec = mb_decode_mimeheader($test_enc);
+		// print "TEST ENC: " . $test_enc . "\n";
 		// back compare decoded
 		$this->assertEquals(
 			$input,
-			$decoded
+			$decoded,
+			"mb_decode_mimeheader"
 		);
+
+		// $this->assertEquals(
+		// 	$input,
+		// 	$test_dec,
+		// 	'mb_encode_to_decode'
+		// );
 	}
 }
 
diff --git a/www/lib/CoreLibs/Convert/MimeEncode.php b/www/lib/CoreLibs/Convert/MimeEncode.php
index 73a3254d..013b27ee 100644
--- a/www/lib/CoreLibs/Convert/MimeEncode.php
+++ b/www/lib/CoreLibs/Convert/MimeEncode.php
@@ -15,6 +15,7 @@ class MimeEncode
 	/**
 	 * wrapper function for mb mime convert
 	 * for correct conversion with long strings
+	 * NOTE: This is only a wrapper for mb_encode_mimeheader to stay compatible
 	 *
 	 * @param  string $string     string to encode
 	 * @param  string $encoding   target encoding
@@ -29,38 +30,9 @@ class MimeEncode
 		$current_internal_encoding = mb_internal_encoding();
 		// set internal encoding, so the mimeheader encode works correctly
 		mb_internal_encoding($encoding);
-		// if a subject, make a work around for the broken mb_mimencode
-		$pos = 0;
-		// after 36 single bytes characters,
-		// if then comes MB, it is broken
-		// has to 2 x 36 < 74 so the mb_encode_mimeheader
-		// 74 hardcoded split does not get triggered
-		$split = 36;
-		$_string = '';
-		while ($pos < mb_strlen($string, $encoding)) {
-			$output = mb_strimwidth($string, $pos, $split, "", $encoding);
-			$pos += mb_strlen($output, $encoding);
-			// if the strinlen is 0 here, get out of the loop
-			if (!mb_strlen($output, $encoding)) {
-				$pos += mb_strlen($string, $encoding);
-			}
-			$_string_encoded = mb_encode_mimeheader($output, $encoding);
-			// only make linebreaks if we have mime encoded code inside
-			// the space only belongs in the second line
-			if ($_string && preg_match("/^=\?/", $_string_encoded)) {
-				$_string .= $line_break . " ";
-			} elseif (
-				// hack for plain text with space at the end
-				mb_strlen($output, $encoding) == $split &&
-				mb_substr($output, -1, 1, $encoding) == " "
-			) {
-				// if output ends with space, add one more
-				$_string_encoded .= " ";
-			}
-			$_string .= $_string_encoded;
-		}
-		// strip out any spaces BEFORE a line break
-		$string = str_replace(" " . $line_break, $line_break, $_string);
+		// use the internal convert to mime header
+		// it works from PHP 8.2 on
+		$string = mb_encode_mimeheader($string, $encoding, 'B', $line_break);
 		// before we end, reset internal encoding
 		mb_internal_encoding($current_internal_encoding);
 		// return mime encoded string