diff --git a/Classes/Service/CleanHtmlService.php b/Classes/Service/CleanHtmlService.php
index 9722fa0..f61a6f6 100644
--- a/Classes/Service/CleanHtmlService.php
+++ b/Classes/Service/CleanHtmlService.php
@@ -104,7 +104,7 @@ public function clean(string $html, array $config = []): string
         }
 
         // convert line-breaks to UNIX
-        $this->convNlOs($html);
+        $html = preg_replace('/\r\n|\r/', $this->newline, $html);
 
         $manipulations = [];
 
@@ -116,16 +116,17 @@ public function clean(string $html, array $config = []): string
             $manipulations['removeComments'] = GeneralUtility::makeInstance(RemoveComments::class);
         }
 
-        if (!empty($this->headerComment)) {
-            $this->includeHeaderComment($html);
-        }
-
         foreach ($manipulations as $key => $manipulation) {
             /** @var ManipulationInterface $manipulation */
             $configuration = isset($config[$key . '.']) && \is_array($config[$key . '.']) ? $config[$key . '.'] : [];
             $html = $manipulation->manipulate($html, $configuration);
         }
 
+        // include configured header comment in HTML content block
+        if (!empty($this->headerComment)) {
+            $html = preg_replace('/^(-->)$/m', "\n\t" . $this->headerComment . "\n$1", $html, 1);
+        }
+
         // cleanup HTML5 self-closing elements
         if (!isset($GLOBALS['TSFE']->config['config']['doctype'])
             || 'x' !== substr($GLOBALS['TSFE']->config['config']['doctype'], 0, 1)) {
@@ -136,13 +137,11 @@ public function clean(string $html, array $config = []): string
             );
         }
 
-        if ($this->formatType > 0) {
-            $html = $this->formatHtml($html);
+        if ($this->formatType) {
+            $indenter = new \Gajus\Dindent\Indenter(['indentation_character' => $this->tab]);
+            $html = $indenter->indent($html);
         }
 
-        // remove white space after line ending
-        $this->rTrimLines($html);
-
         // recover line-breaks
         if (Environment::isWindows()) {
             $html = str_replace($this->newline, "\r\n", $html);
@@ -150,262 +149,4 @@ public function clean(string $html, array $config = []): string
 
         return (string) $html;
     }
-
-    /**
-     * Formats the (X)HTML code:
-     *  - taps according to the hirarchy of the tags
-     *  - removes empty spaces between tags
-     *  - removes linebreaks within tags (spares where necessary: pre, textarea, comments, ..)
-     *  choose from five options:
-     *    0 => off
-     *    1 => no line break at all  (code in one line)
-     *    2 => minimalistic line breaks (structure defining box-elements)
-     *    3 => aesthetic line breaks (important box-elements)
-     *    4 => logic line breaks (all box-elements)
-     *    5 => max line breaks (all elements).
-     */
-    protected function formatHtml(string $html): string
-    {
-        // Save original formated pre, textarea, comments, styles and scripts & replace them with markers
-        preg_match_all(
-            '/(?s)((<!--.*?-->)|(<[ \n\r]*pre[^>]*>.*?<[ \n\r]*\/pre[^>]*>)|(<[ \n\r]*textarea[^>]*>.*?<[ \n\r]*\/textarea[^>]*>)|(<[ \n\r]*style[^>]*>.*?<[ \n\r]*\/style[^>]*>)|(<[ \n\r]*script[^>]*>.*?<[ \n\r]*\/script[^>]*>))/im',
-            $html,
-            $matches
-        );
-        $noFormat = $matches[0]; // do not format these block elements
-        for ($i = 0; $i < \count($noFormat); ++$i) {
-            $html = str_replace($noFormat[$i], "\n<!-- ELEMENT {$i} -->", $html);
-        }
-
-        // define box elements for formatting
-        $trueBoxElements = 'address|blockquote|center|dir|div|dl|fieldset|form|h1|h2|h3|h4|h5|h6|hr|isindex|menu|noframes|noscript|ol|p|pre|table|ul|article|aside|details|figcaption|figure|footer|header|hgroup|menu|nav|section';
-        $functionalBoxElements = 'dd|dt|frameset|li|tbody|td|tfoot|th|thead|tr|colgroup';
-        $usableBoxElements = 'applet|button|del|iframe|ins|map|object|script';
-        $imagineBoxElements = 'html|body|head|meta|title|link|script|base|!--';
-        $allBoxLikeElements = '(?>' . $trueBoxElements . '|' . $functionalBoxElements . '|' . $usableBoxElements . '|' . $imagineBoxElements . ')';
-        $esteticBoxLikeElements = '(?>html|head|body|meta name|title|div|table|h1|h2|h3|h4|h5|h6|p|form|pre|center|!--)';
-        $structureBoxLikeElements = '(?>html|head|body|div|!--)';
-
-        // split html into it's elements
-        $htmlArrayTemp = preg_split(
-            '/(<(?:[^<>]+(?:"[^"]*"|\'[^\']*\')?)+>)/',
-            $html,
-            -1,
-            \PREG_SPLIT_DELIM_CAPTURE | \PREG_SPLIT_NO_EMPTY
-        );
-
-        if (false === $htmlArrayTemp) {
-            // Restore saved comments, styles and scripts
-            for ($i = 0; $i < \count($noFormat); ++$i) {
-                $html = str_replace("<!-- ELEMENT {$i} -->", $noFormat[$i], $html);
-            }
-
-            return $html;
-        }
-        // remove empty lines
-        $htmlArray = [''];
-        $index = 1;
-        for ($x = 0; $x < \count($htmlArrayTemp); ++$x) {
-            $text = trim($htmlArrayTemp[$x]);
-            $htmlArray[$index] = '' !== $text ? $htmlArrayTemp[$x] : $this->emptySpaceChar;
-            ++$index;
-        }
-
-        // rebuild html
-        $html = '';
-        $tabs = 0;
-        for ($x = 0; $x < \count($htmlArray); ++$x) {
-            $htmlArrayBefore = $htmlArray[$x - 1] ?? '';
-            $htmlArrayCurrent = $htmlArray[$x] ?? '';
-
-            // check if the element should stand in a new line
-            $newline = false;
-            if ('<?xml' == substr($htmlArrayBefore, 0, 5)) {
-                $newline = true;
-            } elseif (2 == $this->formatType && ( // minimalistic line break
-                // this element has a line break before itself
-                preg_match(
-                    '/<' . $structureBoxLikeElements . '(.*)>/Usi',
-                    $htmlArrayCurrent
-                ) || preg_match(
-                    '/<' . $structureBoxLikeElements . '(.*) \/>/Usi',
-                    $htmlArrayCurrent
-                ) // one element before is a element that has a line break after
-                || preg_match(
-                    '/<\/' . $structureBoxLikeElements . '(.*)>/Usi',
-                    $htmlArrayBefore
-                ) || '<!--' == substr(
-                    $htmlArrayBefore,
-                    0,
-                    4
-                ) || preg_match('/<' . $structureBoxLikeElements . '(.*) \/>/Usi', $htmlArrayBefore))
-            ) {
-                $newline = true;
-            } elseif (3 == $this->formatType && ( // aestetic line break
-                // this element has a line break before itself
-                preg_match(
-                    '/<' . $esteticBoxLikeElements . '(.*)>/Usi',
-                    $htmlArrayCurrent
-                ) || preg_match(
-                    '/<' . $esteticBoxLikeElements . '(.*) \/>/Usi',
-                    $htmlArrayCurrent
-                ) // one element before is a element that has a line break after
-                || preg_match('/<\/' . $esteticBoxLikeElements . '(.*)>/Usi', $htmlArrayBefore) || '<!--' == substr(
-                    $htmlArrayBefore,
-                    0,
-                    4
-                ) || preg_match('/<' . $esteticBoxLikeElements . '(.*) \/>/Usi', $htmlArrayBefore))
-            ) {
-                $newline = true;
-            } elseif ($this->formatType >= 4 && ( // logical line break
-                // this element has a line break before itself
-                preg_match(
-                    '/<' . $allBoxLikeElements . '(.*)>/Usi',
-                    $htmlArrayCurrent
-                ) || preg_match(
-                    '/<' . $allBoxLikeElements . '(.*) \/>/Usi',
-                    $htmlArrayCurrent
-                ) // one element before is a element that has a line break after
-                || preg_match('/<\/' . $allBoxLikeElements . '(.*)>/Usi', $htmlArrayBefore) || '<!--' == substr(
-                    $htmlArrayBefore,
-                    0,
-                    4
-                ) || preg_match('/<' . $allBoxLikeElements . '(.*) \/>/Usi', $htmlArrayBefore))
-            ) {
-                $newline = true;
-            }
-
-            // count down a tab
-            if ('</' == substr($htmlArrayCurrent, 0, 2)) {
-                --$tabs;
-            }
-
-            // add tabs and line breaks in front of the current tag
-            if ($newline) {
-                $html .= $this->newline;
-                for ($y = 0; $y < $tabs; ++$y) {
-                    $html .= $this->tab;
-                }
-            }
-
-            // remove white spaces and line breaks and add current tag to the html-string
-            if ('<![CDATA[' == substr($htmlArrayCurrent, 0, 9) // remove multiple white space in CDATA / XML
-                || '<?xml' == substr($htmlArrayCurrent, 0, 5)
-            ) {
-                $html .= $this->killWhiteSpace($htmlArrayCurrent);
-            } else { // remove all line breaks
-                $html .= $this->killLineBreaks($htmlArrayCurrent);
-            }
-
-            // count up a tab
-            if ('<' == substr($htmlArrayCurrent, 0, 1) && '/' != substr($htmlArrayCurrent, 1, 1) && '/>' != substr($htmlArrayCurrent, -2)) {
-                if (' ' !== substr($htmlArrayCurrent, 1, 1)
-                    && 'img' !== substr($htmlArrayCurrent, 1, 3)
-                    && 'source' !== substr($htmlArrayCurrent, 1, 6)
-                    && 'br' !== substr($htmlArrayCurrent, 1, 2)
-                    && 'hr' !== substr($htmlArrayCurrent, 1, 2)
-                    && 'input' !== substr($htmlArrayCurrent, 1, 5)
-                    && 'link' !== substr($htmlArrayCurrent, 1, 4)
-                    && 'meta' !== substr($htmlArrayCurrent, 1, 4)
-                    && 'col ' !== substr($htmlArrayCurrent, 1, 4)
-                    && 'frame' !== substr($htmlArrayCurrent, 1, 5)
-                    && 'isindex' !== substr($htmlArrayCurrent, 1, 7)
-                    && 'param' !== substr($htmlArrayCurrent, 1, 5)
-                    && 'area' !== substr($htmlArrayCurrent, 1, 4)
-                    && 'base' !== substr($htmlArrayCurrent, 1, 4)
-                    && '<!' !== substr($htmlArrayCurrent, 0, 2)
-                    && '<?xml' !== substr($htmlArrayCurrent, 0, 5)
-                ) {
-                    ++$tabs;
-                }
-            }
-        }
-
-        // Remove empty lines
-        if ($this->formatType > 1) {
-            $this->removeEmptyLines($html);
-        }
-
-        // Restore saved comments, styles and scripts
-        for ($i = 0; $i < \count($noFormat); ++$i) {
-            $html = str_replace("<!-- ELEMENT {$i} -->", $noFormat[$i], $html);
-        }
-
-        // include debug comment at the end
-        if (0 != $tabs && true === $this->debugComment) {
-            $html .= "<!-- {$tabs} open elements found -->";
-        }
-
-        return $html;
-    }
-
-    /**
-     * Remove ALL line breaks and multiple white space.
-     */
-    protected function killLineBreaks(string $html): string
-    {
-        $html = str_replace($this->newline, '', $html);
-
-        return preg_replace('/\s\s+/u', ' ', $html);
-        // ? return preg_replace('/\n|\s+(\s)/u', '$1', $html);
-    }
-
-    /**
-     * Remove multiple white space, keeps line breaks.
-     */
-    protected function killWhiteSpace(string $html): string
-    {
-        $temp = explode($this->newline, $html);
-        for ($i = 0; $i < \count($temp); ++$i) {
-            if (!trim($temp[$i])) {
-                unset($temp[$i]);
-                continue;
-            }
-
-            $temp[$i] = trim($temp[$i]);
-            $temp[$i] = preg_replace('/\s\s+/', ' ', $temp[$i]);
-        }
-
-        return implode($this->newline, $temp);
-    }
-
-    /**
-     * Remove white space at the end of lines, keeps other white space and line breaks.
-     */
-    protected function rTrimLines(string &$html): void
-    {
-        $html = preg_replace('/\s+$/m', '', $html);
-    }
-
-    /**
-     * Convert newlines according to the current OS.
-     */
-    protected function convNlOs(string &$html): void
-    {
-        $html = preg_replace("(\r\n|\r)", $this->newline, $html);
-    }
-
-    /**
-     * Remove empty lines.
-     */
-    protected function removeEmptyLines(string &$html): void
-    {
-        $temp = explode($this->newline, $html);
-        $result = [];
-        for ($i = 0; $i < \count($temp); ++$i) {
-            if ('' == trim($temp[$i])) {
-                continue;
-            }
-            $result[] = $temp[$i];
-        }
-        $html = implode($this->newline, $result);
-    }
-
-    /**
-     * Include configured header comment in HTML content block.
-     */
-    public function includeHeaderComment(string &$html): void
-    {
-        $html = preg_replace('/^(-->)$/m', "\n\t" . $this->headerComment . "\n$1", $html);
-    }
 }
diff --git a/README.md b/README.md
index 48b9bd8..49b386d 100644
--- a/README.md
+++ b/README.md
@@ -184,7 +184,3 @@ composer install jweiland/replacer
 |:----------------------------------|:------------|:-----------------------------------------------------------------|:-------------------|
 | svgstore.enabled                  | boolean     | Is the SVG extract & merge enabled for this template             | 1                  |
 | svgstore.fileSize                 | integer     | Maximum file size of a SVG to include (in `[byte]`)              | 50000              |
-
----
-##### ToDo:
-- Try external packages like https://github.com/ArjanSchouten/HtmlMinifier
diff --git a/composer.json b/composer.json
index e80e5fe..7339399 100644
--- a/composer.json
+++ b/composer.json
@@ -6,18 +6,14 @@
 	"license": "GPL-2.0-or-later",
 	"require": {
 		"php": "^8.1",
-		"typo3/cms-core": "^12.4||^13.4"
+		"typo3/cms-core": "^12.4||^13.4",
+		"schleuse/dindent": "dev-feature/new-major"
 	},
 	"autoload": {
 		"psr-4": {
 			"HTML\\Sourceopt\\": "Classes/"
 		}
 	},
-	"replace": {
-		"maxserv/replacecontent": "*",
-		"typo3-ter/replacecontent": "*",
-		"typo3-ter/sourceopt": "self.version"
-	},
 	"require-dev": {
 		"typo3/testing-framework": "^8.2",
 		"friendsofphp/php-cs-fixer": "^3.3",
@@ -29,6 +25,14 @@
 			"TYPO3\\CMS\\Core\\Tests\\": ".Build/vendor/typo3/cms/typo3/sysext/core/Tests/"
 		}
 	},
+	"replace": {
+		"maxserv/replacecontent": "*",
+		"typo3-ter/replacecontent": "*",
+		"typo3-ter/sourceopt": "self.version"
+	},
+	"suggest": {
+		"lochmueller/staticfilecache": "A very flexible and very, very, very fast cache to TYPO3"
+	},
 	"config": {
 		"vendor-dir": ".Build/vendor",
 		"bin-dir": ".Build/bin",