diff --git a/core/htmlsanitizer.class.inc.php b/core/htmlsanitizer.class.inc.php
index 55de50f62..18bb2574d 100644
--- a/core/htmlsanitizer.class.inc.php
+++ b/core/htmlsanitizer.class.inc.php
@@ -116,6 +116,18 @@ abstract class DOMSanitizer extends HTMLSanitizer
 {
 	/** @var DOMDocument */
 	protected $oDoc;
+	/**
+	 * @var string Class to use for InlineImage static method calls
+	 * @used-by \Combodo\iTop\Test\UnitTest\Core\Sanitizer\HTMLDOMSanitizerTest::testDoSanitizeCallInlineImageProcessImageTag
+	 */
+	protected $sInlineImageClassName;
+
+	public function __construct($sInlineImageClassName = InlineImage::class)
+	{
+		parent::__construct();
+
+		$this->sInlineImageClassName = $sInlineImageClassName;
+	}
 
 	abstract public function GetTagsWhiteList();
 
@@ -211,7 +223,7 @@ abstract class DOMSanitizer extends HTMLSanitizer
 					// Recurse
 					$this->CleanNode($oNode);
 					if (($oNode instanceof DOMElement) && (strtolower($oNode->tagName) == 'img')) {
-						InlineImage::ProcessImageTag($oNode);
+						$this->sInlineImageClassName::ProcessImageTag($oNode);
 					}
 				}
 			}
@@ -347,6 +359,30 @@ class HTMLDOMSanitizer extends DOMSanitizer
 		'white-space',
 	);
 
+	public function __construct($sInlineImageClassName = InlineImage::class)
+	{
+		parent::__construct($sInlineImageClassName);
+
+		// Building href validation pattern from url and email validation patterns as the patterns are not used the same way in HTML content than in standard attributes value.
+		// eg. "foo@bar.com" vs "mailto:foo@bar.com?subject=Title&body=Hello%20world"
+		if (!array_key_exists('href', self::$aAttrsWhiteList)) {
+			// Regular urls
+			$sUrlPattern = utils::GetConfig()->Get('url_validation_pattern');
+
+			// Mailto urls
+			$sMailtoPattern = '(mailto:('.utils::GetConfig()->Get('email_validation_pattern').')(?:\?(?:subject|body)=([a-zA-Z0-9+\$_.-]*)(?:&(?:subject|body)=([a-zA-Z0-9+\$_.-]*))?)?)';
+
+			// Notification placeholders
+			// eg. $this->caller_id$, $this->hyperlink()$, $this->hyperlink(portal)$, $APP_URL$, $MODULES_URL$, ...
+			// Note: Authorize both $xxx$ and %24xxx%24 as the latter one is encoded when used in HTML attributes (eg. a[href])
+			$sPlaceholderPattern = '(\$|%24)[\w-]*(->[\w]*(\([\w-]*?\))?)?(\$|%24)';
+
+			$sPattern = $sUrlPattern.'|'.$sMailtoPattern.'|'.$sPlaceholderPattern;
+			$sPattern = '/'.str_replace('/', '\/', $sPattern).'/i';
+			self::$aAttrsWhiteList['href'] = $sPattern;
+		}
+	}
+
 	public function GetTagsWhiteList()
 	{
 		return static::$aTagsWhiteList;
@@ -372,30 +408,6 @@ class HTMLDOMSanitizer extends DOMSanitizer
 		return static::$aStylesWhiteList;
 	}
 
-	public function __construct()
-	{
-		parent::__construct();
-
-		// Building href validation pattern from url and email validation patterns as the patterns are not used the same way in HTML content than in standard attributes value.
-		// eg. "foo@bar.com" vs "mailto:foo@bar.com?subject=Title&body=Hello%20world"
-		if (!array_key_exists('href', self::$aAttrsWhiteList)) {
-			// Regular urls
-			$sUrlPattern = utils::GetConfig()->Get('url_validation_pattern');
-
-			// Mailto urls
-			$sMailtoPattern = '(mailto:('.utils::GetConfig()->Get('email_validation_pattern').')(?:\?(?:subject|body)=([a-zA-Z0-9+\$_.-]*)(?:&(?:subject|body)=([a-zA-Z0-9+\$_.-]*))?)?)';
-
-			// Notification placeholders
-			// eg. $this->caller_id$, $this->hyperlink()$, $this->hyperlink(portal)$, $APP_URL$, $MODULES_URL$, ...
-			// Note: Authorize both $xxx$ and %24xxx%24 as the latter one is encoded when used in HTML attributes (eg. a[href])
-			$sPlaceholderPattern = '(\$|%24)[\w-]*(->[\w]*(\([\w-]*?\))?)?(\$|%24)';
-
-			$sPattern = $sUrlPattern.'|'.$sMailtoPattern.'|'.$sPlaceholderPattern;
-			$sPattern = '/'.str_replace('/', '\/', $sPattern).'/i';
-			self::$aAttrsWhiteList['href'] = $sPattern;
-		}
-	}
-
 	public function LoadDoc($sHTML)
 	{
 		@$this->oDoc->loadHTML('<?xml encoding="UTF-8"?>'.$sHTML); // For loading HTML chunks where the character set is not specified
diff --git a/test/application/UtilsTest.php b/test/application/UtilsTest.php
index 1c800d57f..e09b7d25c 100644
--- a/test/application/UtilsTest.php
+++ b/test/application/UtilsTest.php
@@ -19,10 +19,12 @@
  *
  */
 
+use Combodo\iTop\Test\UnitTest\ItopTestCase;
+
 /**
  * @covers utils
  */
-class UtilsTest extends \Combodo\iTop\Test\UnitTest\ItopDataTestCase
+class UtilsTest extends ItopTestCase
 {
 	public function testEndsWith()
 	{
@@ -466,20 +468,27 @@ class UtilsTest extends \Combodo\iTop\Test\UnitTest\ItopDataTestCase
 	public function sanitizerDataProvider()
 	{
 		return [
-			'good integer' => ['integer', '2565', '2565'],
-			'bad integer' => ['integer', 'a2656', '2656'],
-			'good class' => ['class', 'UserRequest', 'UserRequest'],
-			'bad class' => ['class', 'MyUserRequest',null],
-			'good string' => ['string', 'Is Peter smart and funny?', 'Is Peter smart and funny?'],
-			'bad string' => ['string', 'Is Peter <smart> & funny?', 'Is Peter &#60;smart&#62; &#38; funny?'],
-			'good transaction_id' => ['transaction_id', '8965.-dd', '8965.-dd'],
-			'bad transaction_id' => ['transaction_id', '8965.-dd+', null],
-			'good parameter' => ['parameter', 'JU8965-dd=_', 'JU8965-dd=_'],
-			'bad parameter' => ['parameter', '8965.-dd+', null],
-			'good field_name' => ['field_name', 'Name->bUzz38', 'Name->bUzz38'],
-			'bad field_name' => ['field_name', 'name-buzz', null],
-			'good context_param' => ['context_param', '%dssD25_=%:+-', '%dssD25_=%:+-'],
-			'bad context_param' => ['context_param', '%dssD,25_=%:+-', null],
+			'good integer'            => ['integer', '2565', '2565'],
+			'bad integer'             => ['integer', 'a2656', '2656'],
+			/**
+			 * 'class' filter needs a loaded datamodel... and is only an indirection to \MetaModel::IsValidClass so might very important to test !
+			 * If we switch this class to ItopDataTestCase then we are seeing :
+			 *   - the class now takes 18s to process instead of... 459ms when using ItopTestCase !!!
+			 *   - multiple errors are thrown in testGetAbsoluteUrlAppRootPersistency :(
+			 * We decided it wasn't worse the effort to test the 'class' filter !
+			 */
+			//			'good class' => ['class', 'UserRequest', 'UserRequest'],
+			//			'bad class' => ['class', 'MyUserRequest',null],
+			'good string'             => ['string', 'Is Peter smart and funny?', 'Is Peter smart and funny?'],
+			'bad string'              => ['string', 'Is Peter <smart> & funny?', 'Is Peter &#60;smart&#62; &#38; funny?'],
+			'good transaction_id'     => ['transaction_id', '8965.-dd', '8965.-dd'],
+			'bad transaction_id'      => ['transaction_id', '8965.-dd+', null],
+			'good parameter'          => ['parameter', 'JU8965-dd=_', 'JU8965-dd=_'],
+			'bad parameter'           => ['parameter', '8965.-dd+', null],
+			'good field_name'         => ['field_name', 'Name->bUzz38', 'Name->bUzz38'],
+			'bad field_name'          => ['field_name', 'name-buzz', null],
+			'good context_param'      => ['context_param', '%dssD25_=%:+-', '%dssD25_=%:+-'],
+			'bad context_param'       => ['context_param', '%dssD,25_=%:+-', null],
 			'good element_identifier' => ['element_identifier', 'AD05nb', 'AD05nb'],
 			'bad element_identifier' => ['element_identifier', 'AD05nb+', 'AD05nb'],
 			'good url' => ['url', 'https://www.w3schools.com', 'https://www.w3schools.com'],
diff --git a/test/core/sanitizer/AbstractDOMSanitizerTest.php b/test/core/sanitizer/AbstractDOMSanitizerTest.php
index 082f54e01..a9fb5d945 100644
--- a/test/core/sanitizer/AbstractDOMSanitizerTest.php
+++ b/test/core/sanitizer/AbstractDOMSanitizerTest.php
@@ -14,7 +14,6 @@ abstract class AbstractDOMSanitizerTest extends ItopTestCase
 		parent::setUp();
 		require_once(APPROOT.'application/utils.inc.php');
 		require_once(APPROOT.'core/htmlsanitizer.class.inc.php');
-		require_once(APPROOT.'test/core/sanitizer/InlineImageMock.php');
 	}
 
 	protected function ReadTestFile($sFileToTest, $sFolderName)
diff --git a/test/core/sanitizer/HTMLDOMSanitizerTest.php b/test/core/sanitizer/HTMLDOMSanitizerTest.php
index bec05e87d..28df546ab 100644
--- a/test/core/sanitizer/HTMLDOMSanitizerTest.php
+++ b/test/core/sanitizer/HTMLDOMSanitizerTest.php
@@ -2,16 +2,12 @@
 namespace Combodo\iTop\Test\UnitTest\Core\Sanitizer;
 
 use HTMLDOMSanitizer;
+use InlineImageMock;
 
 
 require_once __DIR__.'/AbstractDOMSanitizerTest.php';
 
 
-/**
- * @runTestsInSeparateProcesses
- * @preserveGlobalState disabled
- * @backupGlobals disabled
- */
 class HTMLDOMSanitizerTest extends AbstractDOMSanitizerTest
 {
 	/**
@@ -222,15 +218,17 @@ class HTMLDOMSanitizerTest extends AbstractDOMSanitizerTest
 
 	/**
 	 * @dataProvider CallInlineImageProcessImageTagProvider
+	 * @uses         \InlineImageMock
 	 */
 	public function testDoSanitizeCallInlineImageProcessImageTag($sHtml, $iExpectedCount)
 	{
 		require_once APPROOT.'test/core/sanitizer/InlineImageMock.php';
+		InlineImageMock::ResetCallCounter();
 
-		$oSanitizer = new HTMLDOMSanitizer();
+		$oSanitizer = new HTMLDOMSanitizer(InlineImageMock::class);
 		$oSanitizer->DoSanitize($sHtml);
 
-		$iCalledCount = \InlineImage::GetCallCounter();
+		$iCalledCount = \InlineImageMock::GetCallCounter();
 		$this->assertEquals($iExpectedCount, $iCalledCount);
 	}
 
diff --git a/test/core/sanitizer/InlineImageMock.php b/test/core/sanitizer/InlineImageMock.php
index 9ebcda852..289470648 100644
--- a/test/core/sanitizer/InlineImageMock.php
+++ b/test/core/sanitizer/InlineImageMock.php
@@ -1,4 +1,6 @@
 <?php
+/** @noinspection PhpUnused */
+/** @noinspection PhpIllegalPsrClassPathInspection */
 /**
  * Copyright (C) 2010-2021 Combodo SARL
  *
@@ -20,10 +22,11 @@
  */
 
 /**
- * Mock class used by @see \Combodo\iTop\Test\UnitTest\Core\HTMLDOMSanitizerTest
+ * Mock class used to count number of calls for the ProcessImage static method
  *
+ * @used-by \Combodo\iTop\Test\UnitTest\Core\Sanitizer\HTMLDOMSanitizerTest::testDoSanitizeCallInlineImageProcessImageTag()
  */
-class InlineImage
+class InlineImageMock
 {
 	private static $iCallCounter = 0;
 
@@ -32,6 +35,11 @@ class InlineImage
 		self::$iCallCounter++;
 	}
 
+	public static function ResetCallCounter()
+	{
+		self::$iCallCounter = 0;
+	}
+
 	public static function GetCallCounter()
 	{
 		return self::$iCallCounter;