diff --git a/src/Rector/v8/v1/RefactorVariousGeneralUtilityMethodsRector.php b/src/Rector/v8/v1/RefactorVariousGeneralUtilityMethodsRector.php
new file mode 100644
index 000000000..cc93e7b3f
--- /dev/null
+++ b/src/Rector/v8/v1/RefactorVariousGeneralUtilityMethodsRector.php
@@ -0,0 +1,146 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Ssch\TYPO3Rector\Rector\v8\v1;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr\ArrayDimFetch;
+use PhpParser\Node\Expr\Assign;
+use PhpParser\Node\Expr\BinaryOp\GreaterOrEqual;
+use PhpParser\Node\Expr\BinaryOp\Mul;
+use PhpParser\Node\Expr\BinaryOp\Plus;
+use PhpParser\Node\Expr\ConstFetch;
+use PhpParser\Node\Expr\StaticCall;
+use PhpParser\Node\Expr\Variable;
+use PhpParser\Node\Name;
+use PhpParser\Node\Scalar\LNumber;
+use PhpParser\Node\Scalar\String_;
+use PhpParser\Node\Stmt\Expression;
+use Rector\Core\Rector\AbstractRector;
+use Rector\Core\RectorDefinition\CodeSample;
+use Rector\Core\RectorDefinition\RectorDefinition;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Core\Utility\VersionNumberUtility;
+
+/**
+ * @see https://docs.typo3.org/c/typo3/cms-core/master/en-us/Changelog/8.1/Deprecation-75621-GeneralUtilityMethods.html
+ */
+final class RefactorVariousGeneralUtilityMethodsRector extends AbstractRector
+{
+    /**
+     * @var string
+     */
+    private const COMPAT_VERSION = 'compat_version';
+
+    /**
+     * @var string
+     */
+    private const CONVERT_MICROTIME = 'convertMicrotime';
+
+    /**
+     * @var string
+     */
+    private const RAW_URL_ENCODE_JS = 'rawUrlEncodeJS';
+
+    /**
+     * @var string
+     */
+    private const RAW_URL_ENCODE_FP = 'rawUrlEncodeFP';
+
+    /**
+     * @var string
+     */
+    private const GET_MAXIMUM_PATH_LENGTH = 'getMaximumPathLength';
+
+    /**
+     * @var string
+     */
+    private const LCFIRST = 'lcfirst';
+
+    /**
+     * @var string
+     */
+    private const PARTS = 'parts';
+
+    public function getNodeTypes(): array
+    {
+        return [StaticCall::class];
+    }
+
+    /**
+     * @param StaticCall $node
+     */
+    public function refactor(Node $node): ?Node
+    {
+        if (! $this->isMethodStaticCallOrClassMethodObjectType($node, GeneralUtility::class)) {
+            return null;
+        }
+
+        if (! $this->isNames($node->name, [
+            self::COMPAT_VERSION,
+            self::CONVERT_MICROTIME,
+            self::RAW_URL_ENCODE_JS,
+            self::RAW_URL_ENCODE_FP,
+            self::LCFIRST,
+            self::GET_MAXIMUM_PATH_LENGTH,
+        ])) {
+            return null;
+        }
+
+        switch ($this->getName($node->name)) {
+            case self::COMPAT_VERSION:
+                return new GreaterOrEqual(
+                    $this->createStaticCall(VersionNumberUtility::class, 'convertVersionNumberToInteger', [
+                        new ConstFetch(new Name('TYPO3_branch')),
+                    ]),
+                    $this->createStaticCall(VersionNumberUtility::class, 'convertVersionNumberToInteger', $node->args)
+                );
+            case self::CONVERT_MICROTIME:
+                $funcCall = $this->createFuncCall('explode', [new String_(' '), $node->args[0]->value]);
+                $this->addNodeBeforeNode(new Expression(new Assign(new Variable(self::PARTS), $funcCall)), $node);
+
+                return $this->createFuncCall('round', [
+                    new Mul(new Plus(
+                        new ArrayDimFetch(new Variable(self::PARTS), new LNumber(0)),
+                        new ArrayDimFetch(new Variable(self::PARTS), new LNumber(1))
+                    ), new LNumber(1000)),
+                ]);
+            case self::RAW_URL_ENCODE_JS:
+                return $this->createFuncCall('str_replace', [
+                    '%20',
+                    ' ',
+                    $this->createFuncCall('rawurlencode', $node->args),
+                ]);
+            case self::RAW_URL_ENCODE_FP:
+                return $this->createFuncCall('str_replace', [
+                    '%2F',
+                    '/',
+                    $this->createFuncCall('rawurlencode', $node->args),
+                ]);
+            case self::LCFIRST:
+                return $this->createFuncCall(self::LCFIRST, $node->args);
+            case self::GET_MAXIMUM_PATH_LENGTH:
+                return new ConstFetch(new Name('PHP_MAXPATHLEN'));
+        }
+
+        return null;
+    }
+
+    /**
+     * @codeCoverageIgnore
+     */
+    public function getDefinition(): RectorDefinition
+    {
+        return new RectorDefinition('', [new CodeSample(<<<'PHP'
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+$url = 'https://www.domain.com/';
+$url = GeneralUtility::rawUrlEncodeFP($url);
+PHP
+                , <<<'PHP'
+$url = 'https://www.domain.com/';
+$url = str_replace('%2F', '/', rawurlencode($url));
+PHP
+            )]);
+    }
+}
diff --git a/stubs/Core/Utility/GeneralUtility.php b/stubs/Core/Utility/GeneralUtility.php
index b3241dd6e..a7c391beb 100644
--- a/stubs/Core/Utility/GeneralUtility.php
+++ b/stubs/Core/Utility/GeneralUtility.php
@@ -164,8 +164,9 @@ public static function array2xml_cs(array $array, $docTag = 'phparray', array $o
     {
         // Set default charset unless explicitly specified
         $charset = $charset ?: 'utf-8';
+
         // Return XML:
-        return '<?xml version="1.0" encoding="' . htmlspecialchars($charset) . '" standalone="yes" ?>' . LF . self::array2xml($array, '', 0, $docTag, 0, $options);
+        return '<?xml version="1.0" encoding="'.htmlspecialchars($charset).'" standalone="yes" ?>'.LF.self::array2xml($array, '', 0, $docTag, 0, $options);
     }
 
     public static function array2xml(array $array, $NSprefix = '', $level = 0, $docTag = 'phparray', $spaceInd = 0, array $options = [], array $stackData = []): string
@@ -177,4 +178,40 @@ public static function csvValues(array $row, $delim = ',', $quote = '"'): void
     {
 
     }
+
+    public static function compat_version(): void
+    {
+    }
+
+    public static function convertMicrotime(): void
+    {
+    }
+
+    public static function deHSCentities(): void
+    {
+    }
+
+    public static function slashJS(): void
+    {
+    }
+
+    public static function rawUrlEncodeJS(): void
+    {
+    }
+
+    public static function rawUrlEncodeFP(): void
+    {
+    }
+
+    public static function lcfirst(): void
+    {
+    }
+
+    public static function getMaximumPathLength(): void
+    {
+    }
+
+    public static function wrapJS($string, $_ = null): void
+    {
+    }
 }
diff --git a/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/compat_version.php.inc b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/compat_version.php.inc
new file mode 100644
index 000000000..c9e840e9a
--- /dev/null
+++ b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/compat_version.php.inc
@@ -0,0 +1,16 @@
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+GeneralUtility::compat_version('foobar');
+
+?>
+-----
+<?php
+
+use TYPO3\CMS\Core\Utility\VersionNumberUtility;
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+VersionNumberUtility::convertVersionNumberToInteger(TYPO3_branch) >= VersionNumberUtility::convertVersionNumberToInteger('foobar');
+
+?>
diff --git a/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/convert_microtime.php.inc b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/convert_microtime.php.inc
new file mode 100644
index 000000000..d6b94550c
--- /dev/null
+++ b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/convert_microtime.php.inc
@@ -0,0 +1,16 @@
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+$microtime = GeneralUtility::convertMicrotime('10 00');
+
+?>
+-----
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+$parts = explode(' ', '10 00');
+
+$microtime = round(($parts[0] + $parts[1]) * 1000);
+
+?>
diff --git a/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/get_maximum_path_length.php.inc b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/get_maximum_path_length.php.inc
new file mode 100644
index 000000000..0335c05c5
--- /dev/null
+++ b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/get_maximum_path_length.php.inc
@@ -0,0 +1,15 @@
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+$maximum = GeneralUtility::getMaximumPathLength();
+
+?>
+-----
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+$maximum = PHP_MAXPATHLEN;
+
+?>
diff --git a/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/lcfirst.php.inc b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/lcfirst.php.inc
new file mode 100644
index 000000000..690df6a3f
--- /dev/null
+++ b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/lcfirst.php.inc
@@ -0,0 +1,15 @@
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+$string = GeneralUtility::lcfirst('foo');
+
+?>
+-----
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+$string = lcfirst('foo');
+
+?>
diff --git a/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/raw_url_encode_fp.php.inc b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/raw_url_encode_fp.php.inc
new file mode 100644
index 000000000..d4ff60e82
--- /dev/null
+++ b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/raw_url_encode_fp.php.inc
@@ -0,0 +1,17 @@
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+$url = 'https://www.domain.com/';
+$url = GeneralUtility::rawUrlEncodeFP($url);
+
+?>
+-----
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+$url = 'https://www.domain.com/';
+$url = str_replace('%2F', '/', rawurlencode($url));
+
+?>
diff --git a/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/raw_url_encode_js.php.inc b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/raw_url_encode_js.php.inc
new file mode 100644
index 000000000..fc08b34ba
--- /dev/null
+++ b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/Fixture/raw_url_encode_js.php.inc
@@ -0,0 +1,17 @@
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+$url = 'https://www.domain.com/';
+$url = GeneralUtility::rawUrlEncodeJS($url);
+
+?>
+-----
+<?php
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+$url = 'https://www.domain.com/';
+$url = str_replace('%20', ' ', rawurlencode($url));
+
+?>
diff --git a/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/RefactorVariousGeneralUtilityMethodsRectorTest.php b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/RefactorVariousGeneralUtilityMethodsRectorTest.php
new file mode 100644
index 000000000..3c1949e84
--- /dev/null
+++ b/tests/Rector/v8/v1/RefactorVariousGeneralUtilityMethods/RefactorVariousGeneralUtilityMethodsRectorTest.php
@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Ssch\TYPO3Rector\Tests\Rector\v8\v1\RefactorVariousGeneralUtilityMethods;
+
+use Iterator;
+use Rector\Testing\PHPUnit\AbstractRectorTestCase;
+use Ssch\TYPO3Rector\Rector\v8\v1\RefactorVariousGeneralUtilityMethodsRector;
+use Symplify\SmartFileSystem\SmartFileInfo;
+
+final class RefactorVariousGeneralUtilityMethodsRectorTest extends AbstractRectorTestCase
+{
+    /**
+     * @dataProvider provideDataForTest()
+     */
+    public function test(SmartFileInfo $fileInfo): void
+    {
+        $this->doTestFileInfo($fileInfo);
+    }
+
+    public function provideDataForTest(): Iterator
+    {
+        return $this->yieldFilesFromDirectory(__DIR__ . '/Fixture');
+    }
+
+    protected function getRectorClass(): string
+    {
+        return RefactorVariousGeneralUtilityMethodsRector::class;
+    }
+}