TYPO3 / TYPO3.CMS

                $PM = is_array($arr[$k . '.']) ? '<i class="fa fa-' . ($deeper ? 'minus' : 'plus') . '-square-o"></i>' : '<span class="treeline-icon treeline-icon-join' . ($BTM ? 'bottom' : '') . '"></span>';

                $this->tsStackLog[$v]['icons'] = $depthData . ($first ? '' : $PM);

                if ($this->tsStackLog[$v]['content'] !== '') {

                    $content = str_replace($this->tsStackLog[$v]['content'], $v, $content);

                }

                if (is_array($arr[$k . '.'])) {

                    $this->tsStackLog[$v]['content'] = $this->fixContent($arr[$k . '.'], $this->tsStackLog[$v]['content'], $depthData . ($first ? '' : '<span class="treeline-icon treeline-icon-' . $LN . '"></span>'), 0, $v);

                } else {

        // Traverse array again, this time substitute the unique hash with the red key

        foreach ($arr as $k => $v) {

            if (\TYPO3\CMS\Core\Utility\MathUtility::canBeInterpretedAsInteger($k)) {

                if ($this->tsStackLog[$v]['content'] !== '') {

                    $content = str_replace($v, '<strong style="color:red;">[' . $this->tsStackLog[$v]['key'] . ']</strong>', $content);

                }

            }

        }

        // Return the content