diff --git a/application/exceptions/CoreCannotSaveObjectException.php b/application/exceptions/CoreCannotSaveObjectException.php
index 9e70998fe..d7e4235d9 100644
--- a/application/exceptions/CoreCannotSaveObjectException.php
+++ b/application/exceptions/CoreCannotSaveObjectException.php
@@ -28,14 +28,14 @@ class CoreCannotSaveObjectException extends CoreException
 	 *
 	 * @param array $aContextData containing at least those keys : issues, id, class
 	 */
-	public function __construct($aContextData)
+	public function __construct($aContextData, $oPrevious = null)
 	{
 		$this->aIssues = $aContextData['issues'];
 		$this->iObjectId = $aContextData['id'];
 		$this->sObjectClass = $aContextData['class'];
 
 		$sIssues = implode(', ', $this->aIssues);
-		parent::__construct($sIssues, $aContextData);
+		parent::__construct($sIssues, $aContextData, '', $oPrevious);
 	}
 
 	/**
diff --git a/core/cmdbsource.class.inc.php b/core/cmdbsource.class.inc.php
index 81f35d83e..50a5e1ab4 100644
--- a/core/cmdbsource.class.inc.php
+++ b/core/cmdbsource.class.inc.php
@@ -585,6 +585,11 @@ class CMDBSource
 	 */
 	private static function DBQuery($sSql)
 	{
+		$sShortSQL = str_replace("\n", " ", substr($sSql, 0, 120));
+		if (substr_compare($sShortSQL, "SELECT", 0, strlen("SELECT")) !== 0) {
+			IssueLog::Trace("$sShortSQL", 'cmdbsource');
+		}
+
 		$oKPI = new ExecutionKPI();
 		try
 		{
@@ -668,10 +673,15 @@ class CMDBSource
 	 */
 	private static function StartTransaction()
 	{
+		$aStackTrace = debug_backtrace(DEBUG_BACKTRACE_PROVIDE_OBJECT , 3);
+		$sCaller = 'From '.$aStackTrace[1]['file'].'('.$aStackTrace[1]['line'].'): '.$aStackTrace[2]['class'].'->'.$aStackTrace[2]['function'].'()';
 		$bHasExistingTransactions = self::IsInsideTransaction();
 		if (!$bHasExistingTransactions)
 		{
+			IssueLog::Trace("START TRANSACTION $sCaller", 'cmdbsource');
 			self::DBQuery('START TRANSACTION');
+		} else {
+			IssueLog::Trace("Ignore nested (".self::$m_iTransactionLevel.") START TRANSACTION $sCaller", 'cmdbsource');
 		}
 
 		self::AddTransactionLevel();
@@ -689,9 +699,12 @@ class CMDBSource
 	 */
 	private static function Commit()
 	{
+		$aStackTrace = debug_backtrace(DEBUG_BACKTRACE_PROVIDE_OBJECT , 3);
+		$sCaller = 'From '.$aStackTrace[1]['file'].'('.$aStackTrace[1]['line'].'): '.$aStackTrace[2]['class'].'->'.$aStackTrace[2]['function'].'()';
 		if (!self::IsInsideTransaction())
 		{
 			// should not happen !
+			IssueLog::Error("No Transaction COMMIT $sCaller", 'cmdbsource');
 			throw new MySQLNoTransactionException('Trying to commit transaction whereas none have been started !', null);
 		}
 
@@ -699,8 +712,10 @@ class CMDBSource
 
 		if (self::IsInsideTransaction())
 		{
+			IssueLog::Trace("Ignore nested (".self::$m_iTransactionLevel.") COMMIT $sCaller", 'cmdbsource');
 			return;
 		}
+		IssueLog::Trace("COMMIT $sCaller", 'cmdbsource');
 		self::DBQuery('COMMIT');
 	}
 
@@ -719,17 +734,22 @@ class CMDBSource
 	 */
 	private static function Rollback()
 	{
+		$aStackTrace = debug_backtrace(DEBUG_BACKTRACE_PROVIDE_OBJECT , 3);
+		$sCaller = 'From '.$aStackTrace[1]['file'].'('.$aStackTrace[1]['line'].'): '.$aStackTrace[2]['class'].'->'.$aStackTrace[2]['function'].'()';
 		if (!self::IsInsideTransaction())
 		{
 			// should not happen !
+			IssueLog::Error("No Transaction ROLLBACK $sCaller", 'cmdbsource');
 			throw new MySQLNoTransactionException('Trying to commit transaction whereas none have been started !', null);
 		}
 		self::RemoveLastTransactionLevel();
 		if (self::IsInsideTransaction())
 		{
+			IssueLog::Trace("Ignore nested (".self::$m_iTransactionLevel.") ROLLBACK $sCaller", 'cmdbsource');
 			return;
 		}
 
+		IssueLog::Trace("ROLLBACK $sCaller", 'cmdbsource');
 		self::DBQuery('ROLLBACK');
 	}
 
@@ -779,6 +799,18 @@ class CMDBSource
 		self::$m_iTransactionLevel = 0;
 	}
 
+	public static function IsDeadlockException(Exception $e)
+	{
+		while ($e instanceof Exception) {
+			if (($e instanceof MySQLException) && ($e->getCode() == 1213)) {
+				return true;
+			}
+			$e = $e->getPrevious();
+		}
+		return false;
+	}
+
+
 	public static function GetInsertId()
 	{
 		$iRes = self::$m_oMysqli->insert_id;
diff --git a/core/dbobject.class.php b/core/dbobject.class.php
index 8c14f20fd..a28421fad 100644
--- a/core/dbobject.class.php
+++ b/core/dbobject.class.php
@@ -2778,50 +2778,72 @@ abstract class DBObject implements iDisplay
 			}
 		}
 
+		$iTransactionRetry = 1;
 		$bIsTransactionEnabled = MetaModel::GetConfig()->Get('db_core_transactions_enabled');
-		try
+		if ($bIsTransactionEnabled)
 		{
-			if ($bIsTransactionEnabled)
-			{
-				CMDBSource::Query('START TRANSACTION');
-			}
-
-			// First query built upon on the root class, because the ID must be created first
-			$this->m_iKey = $this->DBInsertSingleTable($sRootClass);
-
-			// Then do the leaf class, if different from the root class
-			if ($sClass != $sRootClass)
-			{
-				$this->DBInsertSingleTable($sClass);
-			}
-
-			// Then do the other classes
-			foreach (MetaModel::EnumParentClasses($sClass) as $sParentClass)
-			{
-				if ($sParentClass == $sRootClass)
-				{
-					continue;
-				}
-				$this->DBInsertSingleTable($sParentClass);
-			}
-
-			$this->OnObjectKeyReady();
-
-			$this->DBWriteLinks();
-			$this->WriteExternalAttributes();
-
-			if ($bIsTransactionEnabled)
-			{
-				CMDBSource::Query('COMMIT');
-			}
+			// TODO Deep clone this object before the transaction (to use it in case of rollback)
+			// $iTransactionRetryCount = MetaModel::GetConfig()->Get('db_core_transactions_retry_count');
+			$iTransactionRetryCount = 1;
+			$iTransactionRetryDelay = MetaModel::GetConfig()->Get('db_core_transactions_retry_delay_ms');
+			$iTransactionRetry = $iTransactionRetryCount;
 		}
-		catch (Exception $e)
-		{
-			if ($bIsTransactionEnabled)
-			{
-				CMDBSource::Query('ROLLBACK');
+		while ($iTransactionRetry > 0) {
+			try {
+				$iTransactionRetry--;
+				if ($bIsTransactionEnabled) {
+					CMDBSource::Query('START TRANSACTION');
+				}
+
+				// First query built upon on the root class, because the ID must be created first
+				$this->m_iKey = $this->DBInsertSingleTable($sRootClass);
+
+				// Then do the leaf class, if different from the root class
+				if ($sClass != $sRootClass) {
+					$this->DBInsertSingleTable($sClass);
+				}
+
+				// Then do the other classes
+				foreach (MetaModel::EnumParentClasses($sClass) as $sParentClass) {
+					if ($sParentClass == $sRootClass) {
+						continue;
+					}
+					$this->DBInsertSingleTable($sParentClass);
+				}
+
+				$this->OnObjectKeyReady();
+
+				$this->DBWriteLinks();
+				$this->WriteExternalAttributes();
+
+				if ($bIsTransactionEnabled) {
+					CMDBSource::Query('COMMIT');
+				}
+				break;
+			}
+			catch (Exception $e) {
+				IssueLog::Error($e->getMessage());
+				if ($bIsTransactionEnabled)
+				{
+					CMDBSource::Query('ROLLBACK');
+					if (!CMDBSource::IsInsideTransaction() && CMDBSource::IsDeadlockException($e))
+					{
+						// Deadlock found when trying to get lock; try restarting transaction (only in main transaction)
+						if ($iTransactionRetry > 0)
+						{
+							// wait and retry
+							IssueLog::Error("Insert TRANSACTION Retrying...");
+							usleep(random_int(1, 5) * 1000 * $iTransactionRetryDelay * ($iTransactionRetryCount - $iTransactionRetry));
+							continue;
+						}
+						else
+						{
+							IssueLog::Error("Insert Deadlock TRANSACTION prevention failed.");
+						}
+					}
+				}
+				throw $e;
 			}
-			throw $e;
 		}
 
 		$this->m_bIsInDB = true;
@@ -3185,9 +3207,11 @@ abstract class DBObject implements iDisplay
 			$bIsTransactionEnabled = MetaModel::GetConfig()->Get('db_core_transactions_enabled');
 			if ($bIsTransactionEnabled)
 			{
-				$iIsTransactionRetryCount = MetaModel::GetConfig()->Get('db_core_transactions_retry_count');
+				// TODO Deep clone this object before the transaction (to use it in case of rollback)
+				// $iTransactionRetryCount = MetaModel::GetConfig()->Get('db_core_transactions_retry_count');
+				$iTransactionRetryCount = 1;
 				$iIsTransactionRetryDelay = MetaModel::GetConfig()->Get('db_core_transactions_retry_delay_ms');
-				$iTransactionRetry = $iIsTransactionRetryCount;
+				$iTransactionRetry = $iTransactionRetryCount;
 			}
 			while ($iTransactionRetry > 0)
 			{
@@ -3275,18 +3299,18 @@ abstract class DBObject implements iDisplay
 				}
 				catch (MySQLException $e)
 				{
+					IssueLog::Error($e->getMessage());
 					if ($bIsTransactionEnabled)
 					{
 						CMDBSource::Query('ROLLBACK');
-						if ($e->getCode() == 1213)
+						if (!CMDBSource::IsInsideTransaction() && CMDBSource::IsDeadlockException($e))
 						{
-							// Deadlock found when trying to get lock; try restarting transaction
-							IssueLog::Error($e->getMessage());
+							// Deadlock found when trying to get lock; try restarting transaction (only in main transaction)
 							if ($iTransactionRetry > 0)
 							{
 								// wait and retry
 								IssueLog::Error("Update TRANSACTION Retrying...");
-								usleep(random_int(1, 5) * 1000 * $iIsTransactionRetryDelay * ($iIsTransactionRetryCount - $iTransactionRetry));
+								usleep(random_int(1, 5) * 1000 * $iIsTransactionRetryDelay * ($iTransactionRetryCount - $iTransactionRetry));
 								continue;
 							}
 							else
@@ -3300,10 +3324,11 @@ abstract class DBObject implements iDisplay
 						'id' => $this->GetKey(),
 						'class' => get_class($this),
 						'issues' => $aErrors
-					));
+					), $e);
 				}
 				catch (CoreCannotSaveObjectException $e)
 				{
+					IssueLog::Error($e->getMessage());
 					if ($bIsTransactionEnabled)
 					{
 						CMDBSource::Query('ROLLBACK');
@@ -3312,6 +3337,7 @@ abstract class DBObject implements iDisplay
 				}
 				catch (Exception $e)
 				{
+					IssueLog::Error($e->getMessage());
 					if ($bIsTransactionEnabled)
 					{
 						CMDBSource::Query('ROLLBACK');
@@ -3514,9 +3540,11 @@ abstract class DBObject implements iDisplay
 		$bIsTransactionEnabled = MetaModel::GetConfig()->Get('db_core_transactions_enabled');
 		if ($bIsTransactionEnabled)
 		{
-			$iIsTransactionRetryCount = MetaModel::GetConfig()->Get('db_core_transactions_retry_count');
-			$iIsTransactionRetryDelay = MetaModel::GetConfig()->Get('db_core_transactions_retry_delay_ms');
-			$iTransactionRetry = $iIsTransactionRetryCount;
+			// TODO Deep clone this object before the transaction (to use it in case of rollback)
+			// $iTransactionRetryCount = MetaModel::GetConfig()->Get('db_core_transactions_retry_count');
+			$iTransactionRetryCount = 1;
+			$iTransactionRetryDelay = MetaModel::GetConfig()->Get('db_core_transactions_retry_delay_ms');
+			$iTransactionRetry = $iTransactionRetryCount;
 		}
 		while ($iTransactionRetry > 0)
 		{
@@ -3539,18 +3567,18 @@ abstract class DBObject implements iDisplay
 			}
 			catch (MySQLException $e)
 			{
+				IssueLog::Error($e->getMessage());
 				if ($bIsTransactionEnabled)
 				{
 					CMDBSource::Query('ROLLBACK');
-					if ($e->getCode() == 1213)
+					if (!CMDBSource::IsInsideTransaction() && CMDBSource::IsDeadlockException($e))
 					{
 						// Deadlock found when trying to get lock; try restarting transaction
-						IssueLog::Error($e->getMessage());
 						if ($iTransactionRetry > 0)
 						{
 							// wait and retry
 							IssueLog::Error("Delete TRANSACTION Retrying...");
-							usleep(random_int(1, 5) * 1000 * $iIsTransactionRetryDelay * ($iIsTransactionRetryCount - $iTransactionRetry));
+							usleep(random_int(1, 5) * 1000 * $iTransactionRetryDelay * ($iTransactionRetryCount - $iTransactionRetry));
 							continue;
 						}
 						else
diff --git a/core/log.class.inc.php b/core/log.class.inc.php
index d100b5d6e..147a82044 100644
--- a/core/log.class.inc.php
+++ b/core/log.class.inc.php
@@ -503,6 +503,7 @@ class FileLog
 	protected function Write($sText, $sLevel = '', $sChannel = '', $aContext = array())
 	{
 		$sTextPrefix = empty($sLevel) ? '' : (str_pad($sLevel, 7).' | ');
+		$sTextPrefix .= str_pad(UserRights::GetUserId(), 5)." | ";
 		$sTextSuffix = empty($sChannel) ? '' : " | $sChannel";
 		$sText = "{$sTextPrefix}{$sText}{$sTextSuffix}";
 		$sLogFilePath = $this->oFileNameBuilder->GetLogFilePath();
diff --git a/core/mutex.class.inc.php b/core/mutex.class.inc.php
index 37310cccb..b94f31bde 100644
--- a/core/mutex.class.inc.php
+++ b/core/mutex.class.inc.php
@@ -242,6 +242,8 @@ class iTopMutex
 	 *
 	 * @throws \Exception
 	 * @throws \MySQLException
+	 *
+	 * @since 2.7.5 3.0.0 N°3968 specify `wait_timeout` for the mutex dedicated connection
 	 */
 	public function InitMySQLSession()
 	{
@@ -254,10 +256,36 @@ class iTopMutex
 
 		$this->hDBLink = CMDBSource::GetMysqliInstance($sServer, $sUser, $sPwd, $sSource, $bTlsEnabled, $sTlsCA, false);
 
-		if (!$this->hDBLink)
-		{
+		if (!$this->hDBLink) {
 			throw new Exception("Could not connect to the DB server (host=$sServer, user=$sUser): ".mysqli_connect_error().' (mysql errno: '.mysqli_connect_errno().')');
 		}
+
+		// Make sure that the server variable `wait_timeout` is at least 86400 seconds for this connection,
+		// since the lock will be released if/when the connection times out.
+		// Source https://dev.mysql.com/doc/refman/5.7/en/locking-functions.html :
+		// > A lock obtained with GET_LOCK() is released explicitly by executing RELEASE_LOCK() or implicitly when your session terminates
+		//
+		// BEWARE: If you want to check the value of this variable, when run from an interactive console `SHOW VARIABLES LIKE 'wait_timeout'`
+		// will actually returns the value of the variable `interactive_timeout` which may be quite different.
+		$sSql = "SHOW VARIABLES LIKE 'wait_timeout'";
+		$result = mysqli_query($this->hDBLink, $sSql);
+		if (!$result) {
+			throw new Exception("Failed to issue MySQL query '".$sSql."': ".mysqli_error($this->hDBLink).' (mysql errno: '.mysqli_errno($this->hDBLink).')');
+		}
+		if ($aRow = mysqli_fetch_array($result, MYSQLI_BOTH)) {
+			$iTimeout = (int)$aRow[1];
+		} else {
+			mysqli_free_result($result);
+			throw new Exception("No result for query '".$sSql."'");
+		}
+		mysqli_free_result($result);
+
+		if ($iTimeout < 86400) {
+			$result = mysqli_query($this->hDBLink, 'SET SESSION wait_timeout=86400');
+			if ($result === false) {
+				throw new Exception("Failed to issue MySQL query '".$sSql."': ".mysqli_error($this->hDBLink).' (mysql errno: '.mysqli_errno($this->hDBLink).')');
+			}
+		}
 	}
 
 
diff --git a/datamodels/2.x/itop-portal-base/dictionaries/en.dict.itop-portal-base.php b/datamodels/2.x/itop-portal-base/dictionaries/en.dict.itop-portal-base.php
index 94a20a71d..54c81f3fe 100644
--- a/datamodels/2.x/itop-portal-base/dictionaries/en.dict.itop-portal-base.php
+++ b/datamodels/2.x/itop-portal-base/dictionaries/en.dict.itop-portal-base.php
@@ -68,6 +68,8 @@ Dict::Add('EN US', 'English', 'English', array(
 Dict::Add('EN US', 'English', 'English', array(
 	'Portal:Form:Caselog:Entry:Close:Tooltip' => 'Close this entry',
 	'Portal:Form:Close:Warning' => 'Do you want to leave this form ? Data entered may be lost',
+	'Portal:Error:ObjectCannotBeCreated' => 'Error: object cannot be created. Check associated objects and attachments before submitting again this form.',
+	'Portal:Error:ObjectCannotBeUpdated' => 'Error: object cannot be updated. Check associated objects and attachments before submitting again this form.',
 ));
 
 // UserProfile brick
diff --git a/datamodels/2.x/itop-portal-base/dictionaries/fr.dict.itop-portal-base.php b/datamodels/2.x/itop-portal-base/dictionaries/fr.dict.itop-portal-base.php
index ff9419f5e..d755e8e50 100644
--- a/datamodels/2.x/itop-portal-base/dictionaries/fr.dict.itop-portal-base.php
+++ b/datamodels/2.x/itop-portal-base/dictionaries/fr.dict.itop-portal-base.php
@@ -67,6 +67,8 @@ Dict::Add('FR FR', 'French', 'Français', array(
 Dict::Add('FR FR', 'French', 'Français', array(
 	'Portal:Form:Caselog:Entry:Close:Tooltip' => 'Fermer cette entrée',
 	'Portal:Form:Close:Warning' => 'Voulez-vous quitter ce formulaire ? Les données saisies seront perdues',
+	'Portal:Error:ObjectCannotBeCreated' => 'Erreur: L\'objet n\'a pas été créé. Vérifiez les objets liés et les attachements avant de soumettre à nouveau le formulaire.',
+	'Portal:Error:ObjectCannotBeUpdated' => 'Erreur: L\'objet n\'a pas été modifié. Vérifiez les objets liés et les attachements avant de soumettre à nouveau le formulaire.',
 ));
 
 // UserProfile brick
diff --git a/datamodels/2.x/itop-portal-base/portal/src/Controller/BrowseBrickController.php b/datamodels/2.x/itop-portal-base/portal/src/Controller/BrowseBrickController.php
index c8c851d9b..474f26b8c 100644
--- a/datamodels/2.x/itop-portal-base/portal/src/Controller/BrowseBrickController.php
+++ b/datamodels/2.x/itop-portal-base/portal/src/Controller/BrowseBrickController.php
@@ -30,6 +30,7 @@ use DBObjectSearch;
 use DBObjectSet;
 use DBSearch;
 use FieldExpression;
+use IssueLog;
 use MetaModel;
 use Symfony\Component\HttpFoundation\JsonResponse;
 use Symfony\Component\HttpFoundation\Request;
@@ -65,6 +66,8 @@ class BrowseBrickController extends BrickController
 	 */
 	public function DisplayAction(Request $oRequest, $sBrickId, $sBrowseMode = null, $sDataLoading = null)
 	{
+		$sPortalId = $this->getParameter('combodo.portal.instance.id');
+
 		/** @var \Combodo\iTop\Portal\Helper\BrowseBrickHelper $oBrowseBrickHelper */
 		$oBrowseBrickHelper = $this->get('browse_brick');
 		/** @var \Combodo\iTop\Portal\Helper\RequestManipulatorHelper $oRequestManipulator */
@@ -266,8 +269,7 @@ class BrowseBrickController extends BrickController
 						// Note : This could be way more simpler if we had a SetInternalParam($sParam, $value) verb
 						$aQueryParams = $aLevelsProperties[$aLevelsPropertiesKeys[$i]]['search']->GetInternalParams();
 						// Note : $iSearchloopMax was initialized on the previous loop
-						for ($j = 0; $j <= $iSearchLoopMax; $j++)
-						{
+						for ($j = 0; $j <= $iSearchLoopMax; $j++) {
 							$aQueryParams['search_value_'.$j] = '%'.$aSearchValues[$j].'%';
 						}
 						$aLevelsProperties[$aLevelsPropertiesKeys[$i]]['search']->SetInternalParams($aQueryParams);
@@ -277,12 +279,11 @@ class BrowseBrickController extends BrickController
 			$oQuery = $aLevelsProperties[$aLevelsPropertiesKeys[0]]['search'];
 
 			// Testing appropriate data loading mode if we are in auto
-			if ($sDataLoading === AbstractBrick::ENUM_DATA_LOADING_AUTO)
-			{
+			if ($sDataLoading === AbstractBrick::ENUM_DATA_LOADING_AUTO) {
 				// - Check how many records there is.
 				// - Update $sDataLoading with its new value regarding the number of record and the threshold
 				$oCountSet = new DBObjectSet($oQuery);
-				$fThreshold = (float)MetaModel::GetModuleSetting($this->getParameter('combodo.portal.instance.id'),
+				$fThreshold = (float)MetaModel::GetModuleSetting($sPortalId,
 					'lazy_loading_threshold');
 				$sDataLoading = ($oCountSet->Count() > $fThreshold) ? AbstractBrick::ENUM_DATA_LOADING_LAZY : AbstractBrick::ENUM_DATA_LOADING_FULL;
 				unset($oCountSet);
@@ -440,17 +441,21 @@ class BrowseBrickController extends BrickController
 			}
 		}
 
+		IssueLog::Debug('Portal BrowseBrick query', 'portal', array(
+			'portalId' => $sPortalId,
+			'brickId' => $sBrickId,
+			'oql' => $oSet->GetFilter()->ToOQL(),
+		));
+
+
 		// Preparing response
-		if ($oRequest->isXmlHttpRequest())
-		{
+		if ($oRequest->isXmlHttpRequest()) {
 			$aData = $aData + array(
 					'data' => $aItems,
 					'levelsProperties' => $aLevelsProperties,
 				);
 			$oResponse = new JsonResponse($aData);
-		}
-		else
-		{
+		} else {
 			$aData = $aData + array(
 					'oBrick' => $oBrick,
 					'sBrickId' => $sBrickId,
diff --git a/datamodels/2.x/itop-portal-base/portal/src/Controller/ManageBrickController.php b/datamodels/2.x/itop-portal-base/portal/src/Controller/ManageBrickController.php
index e634fa76f..dfc1a59e1 100644
--- a/datamodels/2.x/itop-portal-base/portal/src/Controller/ManageBrickController.php
+++ b/datamodels/2.x/itop-portal-base/portal/src/Controller/ManageBrickController.php
@@ -42,6 +42,7 @@ use Dict;
 use Exception;
 use FieldExpression;
 use iPopupMenuExtension;
+use IssueLog;
 use JSButtonItem;
 use MetaModel;
 use Symfony\Component\HttpFoundation\JsonResponse;
@@ -89,10 +90,10 @@ class ManageBrickController extends BrickController
 		/** @var \Combodo\iTop\Portal\Brick\ManageBrick $oBrick */
 		$oBrick = $oBrickCollection->GetBrickById($sBrickId);
 
-		if (is_null($sDisplayMode))
-		{
+		if (is_null($sDisplayMode)) {
 			$sDisplayMode = $oBrick->GetDefaultDisplayMode();
 		}
+
 		$aData = $this->GetData($oRequest, $sBrickId, $sGroupingTab, $oBrick::AreDetailsNeededForDisplayMode($sDisplayMode));
 
 		$aExportFields = $oBrick->GetExportFields();
@@ -102,8 +103,7 @@ class ManageBrickController extends BrickController
 				'iDefaultListLength' => $oBrick->GetDefaultListLength(),
 			);
 		// Preparing response
-		if ($oRequest->isXmlHttpRequest())
-		{
+		if ($oRequest->isXmlHttpRequest()) {
 			$oResponse = new JsonResponse($aData);
 		}
 		else
@@ -815,30 +815,31 @@ class ManageBrickController extends BrickController
 					'aColumnsDefinition' => $aColumnsDefinition,
 				);
 			}
-		}
-		else
-		{
+
+			IssueLog::Debug('Portal ManageBrick query', 'portal', array(
+				'portalId' => $sPortalId,
+				'brickId' => $sBrickId,
+				'groupingTab' => $sGroupingTab,
+				'oql' => $oSet->GetFilter()->ToOQL(),
+				'aGroupingTabs' => $aGroupingTabs,
+			));
+		} else {
 			$aGroupingAreasData = array();
 			$sGroupingArea = null;
 		}
 
 		// Preparing response
-		if ($oRequest->isXmlHttpRequest())
-		{
+		if ($oRequest->isXmlHttpRequest()) {
 			$aData = $aData + array(
 					'data' => $aGroupingAreasData[$sGroupingArea]['aItems'],
 				);
-		}
-		else
-		{
+		} else {
 			$aDisplayValues = array();
 			$aUrls = array();
 			$aColumns = array();
 			$aNames = array();
-			if ($bHasScope)
-			{
-				foreach ($aGroupingTabsValues as $aValues)
-				{
+			if ($bHasScope) {
+				foreach ($aGroupingTabsValues as $aValues) {
 					$aDisplayValues[] = array(
 						'value' => $aValues['count'],
 						'label' => $aValues['label'],
diff --git a/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php b/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php
index c1b3ba073..043ad462f 100644
--- a/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php
+++ b/datamodels/2.x/itop-portal-base/portal/src/Form/ObjectFormManager.php
@@ -25,14 +25,12 @@ use AttributeDateTime;
 use AttributeTagSet;
 use CMDBChangeOpAttachmentAdded;
 use CMDBChangeOpAttachmentRemoved;
-use CMDBSource;
 use Combodo\iTop\Form\Field\Field;
 use Combodo\iTop\Form\Field\FileUploadField;
 use Combodo\iTop\Form\Field\LabelField;
 use Combodo\iTop\Form\Form;
 use Combodo\iTop\Form\FormManager;
 use Combodo\iTop\Portal\Helper\ApplicationHelper;
-use CoreCannotSaveObjectException;
 use DBObject;
 use DBObjectSearch;
 use DBObjectSet;
@@ -1121,30 +1119,28 @@ class ObjectFormManager extends FormManager
 			return $aData;
 		}
 
-		// The try catch is essentially to start a MySQL transaction in order to ensure that all or none objects are persisted when creating an object with links
-		try
-		{
-			$sObjectClass = get_class($this->oObject);
+		$sObjectClass = get_class($this->oObject);
 
-			// Starting transaction
-			CMDBSource::Query('START TRANSACTION');
+		try {
 			// Forcing allowed writing on the object if necessary. This is used in some particular cases.
 			$bAllowWrite = ($sObjectClass === 'Person' && $this->oObject->GetKey() == UserRights::GetContactId());
-			if ($bAllowWrite)
-			{
+			if ($bAllowWrite) {
 				$this->oObject->AllowWrite(true);
 			}
 
 			// Writing object to DB
-			$bActivateTriggers = (!$this->oObject->IsNew() && $this->oObject->IsModified());
+			$bIsNew = $this->oObject->IsNew();
 			$bWasModified = $this->oObject->IsModified();
+			$bActivateTriggers = (!$bIsNew && $bWasModified);
 			try
 			{
 				$this->oObject->DBWrite();
 			}
-			catch (CoreCannotSaveObjectException $e)
-			{
-				throw new Exception($e->getHtmlMessage());
+			catch (Exception $e) {
+				if ($bIsNew) {
+					throw new Exception(Dict::S('Portal:Error:ObjectCannotBeCreated'));
+				}
+				throw new Exception(Dict::S('Portal:Error:ObjectCannotBeUpdated'));
 			}
 			// Finalizing images link to object, otherwise it will be cleaned by the GC
 			InlineImage::FinalizeInlineImages($this->oObject);
@@ -1155,9 +1151,6 @@ class ObjectFormManager extends FormManager
 				$this->FinalizeAttachments($aArgs['attachmentIds']);
 			}
 
-			// Ending transaction with a commit as everything was fine
-			CMDBSource::Query('COMMIT');
-
 			// Checking if we have to apply a stimulus
 			if (isset($aArgs['applyStimulus']))
 			{
@@ -1205,14 +1198,11 @@ class ObjectFormManager extends FormManager
 		}
 		catch (Exception $e)
 		{
-			// End transaction with a rollback as something failed
-			CMDBSource::Query('ROLLBACK');
 			$aData['valid'] = false;
 			$aData['messages']['error'] += array('_main' => array($e->getMessage()));
-			IssueLog::Error(__METHOD__.' at line '.__LINE__.' : Rollback during submit ('.$e->getMessage().')');
+			IssueLog::Error(__METHOD__.' at line '.__LINE__.' : '.$e->getMessage());
 		}
 
-
 		return $aData;
 	}