diff --git a/administrator/language/en-GB/en-GB.plg_system_debug.ini b/administrator/language/en-GB/en-GB.plg_system_debug.ini
index 7b3353d082504..ab78291512957 100644
--- a/administrator/language/en-GB/en-GB.plg_system_debug.ini
+++ b/administrator/language/en-GB/en-GB.plg_system_debug.ini
@@ -3,7 +3,10 @@
 ; License GNU General Public License version 2 or later; see LICENSE.txt, see LICENSE.php
 ; Note : All ini files need to be saved as UTF-8 - No BOM
 
+PLG_DEBUG_BYTES="Bytes"
+PLG_DEBUG_CALL_STACK="Call Stack"
 PLG_DEBUG_ERRORS="Errors"
+PLG_DEBUG_EXPLAIN="Explain"
 PLG_DEBUG_FIELD_ALLOWED_GROUPS_DESC="Optionally restrict users that can see debug information to those in the selected user groups. If none selected, all users see the debug information."
 PLG_DEBUG_FIELD_ALLOWED_GROUPS_LABEL="Allowed Groups"
 PLG_DEBUG_FIELD_LANGUAGE_ERRORFILES_DESC="Display a list of the language files that are in error according to the Joomla ini specification."
@@ -12,6 +15,8 @@ PLG_DEBUG_FIELD_LANGUAGE_FILES_DESC="Display a list of the language files that J
 PLG_DEBUG_FIELD_LANGUAGE_FILES_LABEL="Show Language Files"
 PLG_DEBUG_FIELD_LANGUAGE_STRING_DESC="Display a list of the untranslated language strings."
 PLG_DEBUG_FIELD_LANGUAGE_STRING_LABEL="Show Language String"
+PLG_DEBUG_FIELD_LOGS_DESC="Display a list of logged messages."
+PLG_DEBUG_FIELD_LOGS_LABEL="Show Log Entries"
 PLG_DEBUG_FIELD_LOG_CATEGORIES_DESC="A comma separated list of log categories to include. Common log categories include but are not limited to: database, databasequery, deprecated, and jerror.  If empty, all categories will be shown."
 PLG_DEBUG_FIELD_LOG_CATEGORIES_LABEL="Log Categories"
 PLG_DEBUG_FIELD_LOG_CATEGORY_MODE_DESC="Select whether the listed categories should be included or excluded."
@@ -31,8 +36,6 @@ PLG_DEBUG_FIELD_LOG_PRIORITIES_INFO="Info"
 PLG_DEBUG_FIELD_LOG_PRIORITIES_LABEL="Log Priorities"
 PLG_DEBUG_FIELD_LOG_PRIORITIES_NOTICE="Notice"
 PLG_DEBUG_FIELD_LOG_PRIORITIES_WARNING="Warning"
-PLG_DEBUG_FIELD_LOGS_DESC="Display a list of logged messages."
-PLG_DEBUG_FIELD_LOGS_LABEL="Show Log Entries"
 PLG_DEBUG_FIELD_MEMORY_DESC="Display the total memory usage."
 PLG_DEBUG_FIELD_MEMORY_LABEL="Show Memory Usage"
 PLG_DEBUG_FIELD_PROFILING_DESC="Display the profiling waypoints."
@@ -47,24 +50,43 @@ PLG_DEBUG_FIELD_STRIP_PREFIX_DESC="Strip words from the beginning of the string.
 PLG_DEBUG_FIELD_STRIP_PREFIX_LABEL="Strip From Start"
 PLG_DEBUG_FIELD_STRIP_SUFFIX_DESC="Strip words from the end of the string. For multiple words, use the format: (word1|word2)"
 PLG_DEBUG_FIELD_STRIP_SUFFIX_LABEL="Strip From End"
-PLG_DEBUG_LANG_LOADED="Loaded"
-PLG_DEBUG_LANG_NOT_LOADED="Not loaded"
 PLG_DEBUG_LANGUAGE_FIELDSET_LABEL="Language Options"
 PLG_DEBUG_LANGUAGE_FILES_IN_ERROR="Parsing errors in language files"
 PLG_DEBUG_LANGUAGE_FILES_LOADED="Language Files Loaded"
+PLG_DEBUG_LANG_LOADED="Loaded"
+PLG_DEBUG_LANG_NOT_LOADED="Not loaded"
+PLG_DEBUG_LINK_FORMAT="Add xdebug.file_link_format directive to your php.ini file to have links for files"
 PLG_DEBUG_LOGGING_FIELDSET_LABEL="Logging"
 PLG_DEBUG_LOGS="Log Messages"
+PLG_DEBUG_MEMORY="Memory"
+PLG_DEBUG_MEMORY_USED_FOR_QUERY="Query memory: %s Memory before query: %s"
 PLG_DEBUG_MEMORY_USAGE="Memory Usage"
+PLG_DEBUG_NO_PROFILE="No SHOW PROFILE (maybe because there are more than 100 queries)"
 PLG_DEBUG_OTHER_QUERIES="OTHER Tables:"
+PLG_DEBUG_PROFILE="Profile"
 PLG_DEBUG_PROFILE_INFORMATION="Profile Information"
 PLG_DEBUG_QUERIES="Database Queries"
 PLG_DEBUG_QUERIES_LOGGED="%d Queries Logged"
+PLG_DEBUG_QUERIES_TIME="Database queries total: %s"
+PLG_DEBUG_QUERY_AFTER_LAST="After last query: %s"
+PLG_DEBUG_QUERY_DUPLICATES="Duplicate queries"
+PLG_DEBUG_QUERY_DUPLICATES_FOUND="Duplicate found!"
+PLG_DEBUG_QUERY_DUPLICATES_NUMBER="%s duplicates"
+PLG_DEBUG_QUERY_DUPLICATES_TOTAL_NUMBER="%s duplicate found!"
+PLG_DEBUG_QUERY_EXPLAIN_NOT_POSSIBLE="EXPLAIN not possible on query: %s"
+PLG_DEBUG_QUERY_TIME="Query Time: %s"
 PLG_DEBUG_QUERY_TYPES_LOGGED="%d Query Types Logged, Sorted by Occurrences."
 PLG_DEBUG_QUERY_TYPE_AND_OCCURRENCES="%2$d × %1$s"
+PLG_DEBUG_ROWS_RETURNED_BY_QUERY="Rows returned: %s"
 PLG_DEBUG_SELECT_QUERIES="SELECT Tables:"
 PLG_DEBUG_SESSION="Session"
+PLG_DEBUG_TIME="Time"
 PLG_DEBUG_TITLE="Joomla! Debug Console"
 PLG_DEBUG_UNKNOWN_FILE="Unknown file"
 PLG_DEBUG_UNTRANSLATED_STRINGS="Untranslated Strings"
+PLG_DEBUG_WARNING_NO_INDEX="NO INDEX KEY COULD BE USED"
+PLG_DEBUG_WARNING_NO_INDEX_DESC="This table has probably a missing index on WHERE equalities and/or JOIN ON column(s) or is written in a way that no index can be used, causing a time-consuming full table scan"
+PLG_DEBUG_WARNING_USING_FILESORT="Using filesort"
+PLG_DEBUG_WARNING_USING_FILESORT_DESC="This table has probably a missing index on WHERE/ON equality column(s) ending by the ORDER BY column(s) or is written in a way that no index can be used, causing a time-consuming filesort."
 PLG_DEBUG_XML_DESCRIPTION="This plugin provides a variety of system information as well as assistance for the creation of translation files."
 PLG_SYSTEM_DEBUG="System - Debug"
diff --git a/libraries/joomla/database/driver.php b/libraries/joomla/database/driver.php
index 1cbaa5ec917d1..dd3d0764eeb34 100644
--- a/libraries/joomla/database/driver.php
+++ b/libraries/joomla/database/driver.php
@@ -92,6 +92,19 @@ abstract class JDatabaseDriver extends JDatabase implements JDatabaseInterface
 	 */
 	protected $log = array();
 
+	/**
+	 * @var    array  The log of executed SQL statements timings (start and stop microtimes) by the database driver.
+	 * @since  CMS 3.1.2
+	 */
+	protected $timings = array();
+
+
+	/**
+	 * @var    array  The log of executed SQL statements timings (start and stop microtimes) by the database driver.
+	 * @since  CMS 3.1.2
+	 */
+	protected $callStacks = array();
+
 	/**
 	 * @var    string  The character(s) used to quote SQL statement names such as table names or field names,
 	 *                 etc.  The child classes should define this as necessary.  If a single character string the
@@ -170,6 +183,12 @@ abstract class JDatabaseDriver extends JDatabase implements JDatabaseInterface
 	 */
 	protected $transactionDepth = 0;
 
+	/**
+	 * @var    callable[]  List of callables to call just before disconnecting database
+	 * @since  CMS 3.1.2
+	 */
+	protected $disconnectHandlers = array();
+
 	/**
 	 * Get a list of available database connectors.  The list will only be populated with connectors that both
 	 * the class exists and the static test method returns true.  This gives us the ability to have a multitude
@@ -464,6 +483,19 @@ public function createDatabase($options, $utf = true)
 	 */
 	abstract public function disconnect();
 
+	/**
+	 * Adds a function callable just before disconnecting the database. Parameter of the callable is $this JDatabaseDriver
+	 *
+	 * @param   callable  $callable  Function to call in disconnect() method just before disconnecting from database
+	 * @return  void
+	 *
+	 * @since   CMS 3.1.2
+	 */
+	public function addDisconnectHandler($callable)
+	{
+		$this->disconnectHandlers[] = $callable;
+	}
+
 	/**
 	 * Drops a table from the database.
 	 *
@@ -648,6 +680,30 @@ public function getLog()
 		return $this->log;
 	}
 
+	/**
+	 * Get the database driver SQL statement log.
+	 *
+	 * @return  array  SQL statements executed by the database driver.
+	 *
+	 * @since   CMS 3.1.2
+	 */
+	public function getTimings()
+	{
+		return $this->timings;
+	}
+
+	/**
+	 * Get the database driver SQL statement log.
+	 *
+	 * @return  array  SQL statements executed by the database driver.
+	 *
+	 * @since   CMS 3.1.2
+	 */
+	public function getCallStacks()
+	{
+		return $this->callStacks;
+	}
+
 	/**
 	 * Get the minimum supported database version.
 	 *
diff --git a/libraries/joomla/database/driver/mysql.php b/libraries/joomla/database/driver/mysql.php
index b6fe969672438..dc8800a5af0c0 100644
--- a/libraries/joomla/database/driver/mysql.php
+++ b/libraries/joomla/database/driver/mysql.php
@@ -54,10 +54,7 @@ public function __construct($options)
 	 */
 	public function __destruct()
 	{
-		if (is_resource($this->connection))
-		{
-			mysql_close($this->connection);
-		}
+		$this->disconnect();
 	}
 
 	/**
@@ -98,6 +95,12 @@ public function connect()
 
 		// Set charactersets (needed for MySQL 4.1.2+).
 		$this->setUTF();
+
+		// Turn MySQL profiling ON in debug mode:
+		if ($this->debug)
+		{
+			mysqli_query($this->connection, "SET profiling = 1;");
+		}
 	}
 
 	/**
@@ -110,7 +113,15 @@ public function connect()
 	public function disconnect()
 	{
 		// Close the connection.
-		mysql_close($this->connection);
+		if (is_resource($this->connection))
+		{
+			foreach ($this->disconnectHandlers as $h)
+			{
+				call_user_func_array($h, array( &$this));
+			}
+
+			mysql_close($this->connection);
+		}
 
 		$this->connection = null;
 	}
@@ -254,6 +265,10 @@ public function execute()
 		// Increment the query counter.
 		$this->count++;
 
+		// Reset the error values.
+		$this->errorNum = 0;
+		$this->errorMsg = '';
+
 		// If debugging is enabled then let's log the query.
 		if ($this->debug)
 		{
@@ -261,15 +276,19 @@ public function execute()
 			$this->log[] = $query;
 
 			JLog::add($query, JLog::DEBUG, 'databasequery');
-		}
 
-		// Reset the error values.
-		$this->errorNum = 0;
-		$this->errorMsg = '';
+			$this->timings[] = microtime(true);
+		}
 
 		// Execute the query. Error suppression is used here to prevent warnings/notices that the connection has been lost.
 		$this->cursor = @mysql_query($query, $this->connection);
 
+		if ($this->debug)
+		{
+			$this->timings[] = microtime(true);
+			$this->callStacks[] = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
+		}
+
 		// If an error occurred handle it.
 		if (!$this->cursor)
 		{
diff --git a/libraries/joomla/database/driver/mysqli.php b/libraries/joomla/database/driver/mysqli.php
index 9cf5181f70678..82a6207f5be4d 100644
--- a/libraries/joomla/database/driver/mysqli.php
+++ b/libraries/joomla/database/driver/mysqli.php
@@ -82,10 +82,7 @@ public function __construct($options)
 	 */
 	public function __destruct()
 	{
-		if (is_callable(array($this->connection, 'close')))
-		{
-			mysqli_close($this->connection);
-		}
+		$this->disconnect();
 	}
 
 	/**
@@ -157,6 +154,13 @@ public function connect()
 
 		// Set charactersets (needed for MySQL 4.1.2+).
 		$this->setUTF();
+
+		// Turn MySQL profiling ON in debug mode:
+		if ($this->debug)
+		{
+			mysqli_query($this->connection, "SET profiling_history_size = 100;");
+			mysqli_query($this->connection, "SET profiling = 1;");
+		}
 	}
 
 	/**
@@ -169,8 +173,13 @@ public function connect()
 	public function disconnect()
 	{
 		// Close the connection.
-		if (is_callable($this->connection, 'close'))
+		if ($this->connection)
 		{
+			foreach ($this->disconnectHandlers as $h)
+			{
+				call_user_func_array($h, array( &$this));
+			}
+
 			mysqli_close($this->connection);
 		}
 
@@ -496,6 +505,11 @@ public function execute()
 		// Increment the query counter.
 		$this->count++;
 
+		// Reset the error values.
+		$this->errorNum = 0;
+		$this->errorMsg = '';
+		$memoryBefore = null;
+
 		// If debugging is enabled then let's log the query.
 		if ($this->debug)
 		{
@@ -503,15 +517,26 @@ public function execute()
 			$this->log[] = $query;
 
 			JLog::add($query, JLog::DEBUG, 'databasequery');
-		}
 
-		// Reset the error values.
-		$this->errorNum = 0;
-		$this->errorMsg = '';
+			$this->timings[] = microtime(true);
+
+			if (is_object($this->cursor))
+			{
+				$this->freeResult();
+			}
+			$memoryBefore = memory_get_usage();
+		}
 
 		// Execute the query. Error suppression is used here to prevent warnings/notices that the connection has been lost.
 		$this->cursor = @mysqli_query($this->connection, $query);
 
+		if ($this->debug)
+		{
+			$this->timings[] = microtime(true);
+			$this->callStacks[] = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
+			$this->callStacks[count($this->callStacks) - 1][0]['memory'] = array($memoryBefore, memory_get_usage(), is_object($this->cursor) ? $this->getNumRows() : null);
+		}
+
 		// If an error occurred handle it.
 		if (!$this->cursor)
 		{
@@ -757,6 +782,10 @@ protected function fetchObject($cursor = null, $class = 'stdClass')
 	protected function freeResult($cursor = null)
 	{
 		mysqli_free_result($cursor ? $cursor : $this->cursor);
+		if ((! $cursor) || ($cursor === $this->cursor))
+		{
+			$this->cursor = null;
+		}
 	}
 
 	/**
diff --git a/libraries/joomla/database/driver/pdo.php b/libraries/joomla/database/driver/pdo.php
index 91245a009bc13..15a9d8cd941ac 100644
--- a/libraries/joomla/database/driver/pdo.php
+++ b/libraries/joomla/database/driver/pdo.php
@@ -90,8 +90,7 @@ public function __construct($options)
 	 */
 	public function __destruct()
 	{
-		$this->freeResult();
-		unset($this->connection);
+		$this->disconnect();
 	}
 
 	/**
@@ -307,6 +306,11 @@ public function connect()
 	 */
 	public function disconnect()
 	{
+		foreach ($this->disconnectHandlers as $h)
+		{
+			call_user_func_array($h, array( &$this));
+		}
+
 		$this->freeResult();
 		unset($this->connection);
 	}
@@ -374,6 +378,10 @@ public function execute()
 		// Increment the query counter.
 		$this->count++;
 
+		// Reset the error values.
+		$this->errorNum = 0;
+		$this->errorMsg = '';
+
 		// If debugging is enabled then let's log the query.
 		if ($this->debug)
 		{
@@ -381,11 +389,9 @@ public function execute()
 			$this->log[] = $query;
 
 			JLog::add($query, JLog::DEBUG, 'databasequery');
-		}
 
-		// Reset the error values.
-		$this->errorNum = 0;
-		$this->errorMsg = '';
+			$this->timings[] = microtime(true);
+		}
 
 		// Execute the query.
 		$this->executed = false;
@@ -404,6 +410,12 @@ public function execute()
 			$this->executed = $this->prepared->execute();
 		}
 
+		if ($this->debug)
+		{
+			$this->timings[] = microtime(true);
+			$this->callStacks[] = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
+		}
+
 		// If an error occurred handle it.
 		if (!$this->executed)
 		{
diff --git a/libraries/joomla/database/driver/postgresql.php b/libraries/joomla/database/driver/postgresql.php
index cee7acd4ac3bf..3729e64dd5c75 100644
--- a/libraries/joomla/database/driver/postgresql.php
+++ b/libraries/joomla/database/driver/postgresql.php
@@ -84,10 +84,7 @@ public function __construct( $options )
 	 */
 	public function __destruct()
 	{
-		if (is_resource($this->connection))
-		{
-			pg_close($this->connection);
-		}
+		$this->disconnect();
 	}
 
 	/**
@@ -136,6 +133,11 @@ public function disconnect()
 		// Close the connection.
 		if (is_resource($this->connection))
 		{
+			foreach ($this->disconnectHandlers as $h)
+			{
+				call_user_func_array($h, array( &$this));
+			}
+
 			pg_close($this->connection);
 		}
 
@@ -532,7 +534,7 @@ public function getVersion()
 	 *
 	 * @example with insertid() call:
 	 *		$query = $this->getQuery(true)
-	 *			insert('jos_dbtest')
+	 *			->insert('jos_dbtest')
 	 *			->columns('title,start_date,description')
 	 *			->values("'testTitle2nd','1971-01-01','testDescription2nd'");
 	 *		$this->setQuery($query);
@@ -628,6 +630,10 @@ public function execute()
 		// Increment the query counter.
 		$this->count++;
 
+		// Reset the error values.
+		$this->errorNum = 0;
+		$this->errorMsg = '';
+
 		// If debugging is enabled then let's log the query.
 		if ($this->debug)
 		{
@@ -635,15 +641,19 @@ public function execute()
 			$this->log[] = $query;
 
 			JLog::add($query, JLog::DEBUG, 'databasequery');
-		}
 
-		// Reset the error values.
-		$this->errorNum = 0;
-		$this->errorMsg = '';
+			$this->timings[] = microtime(true);
+		}
 
 		// Execute the query. Error suppression is used here to prevent warnings/notices that the connection has been lost.
 		$this->cursor = @pg_query($this->connection, $query);
 
+		if ($this->debug)
+		{
+			$this->timings[] = microtime(true);
+			$this->callStacks[] = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
+		}
+
 		// If an error occurred handle it.
 		if (!$this->cursor)
 		{
diff --git a/libraries/joomla/database/driver/sqlsrv.php b/libraries/joomla/database/driver/sqlsrv.php
index 64ca5bd580d31..f1e4a407bbb67 100644
--- a/libraries/joomla/database/driver/sqlsrv.php
+++ b/libraries/joomla/database/driver/sqlsrv.php
@@ -92,10 +92,7 @@ public function __construct($options)
 	 */
 	public function __destruct()
 	{
-		if (is_resource($this->connection))
-		{
-			sqlsrv_close($this->connection);
-		}
+		$this->disconnect();
 	}
 
 	/**
@@ -155,6 +152,11 @@ public function disconnect()
 		// Close the connection.
 		if (is_resource($this->connection))
 		{
+			foreach ($this->disconnectHandlers as $h)
+			{
+				call_user_func_array($h, array( &$this));
+			}
+
 			sqlsrv_close($this->connection);
 		}
 
@@ -581,6 +583,10 @@ public function execute()
 		// Increment the query counter.
 		$this->count++;
 
+		// Reset the error values.
+		$this->errorNum = 0;
+		$this->errorMsg = '';
+
 		// If debugging is enabled then let's log the query.
 		if ($this->debug)
 		{
@@ -588,11 +594,9 @@ public function execute()
 			$this->log[] = $query;
 
 			JLog::add($query, JLog::DEBUG, 'databasequery');
-		}
 
-		// Reset the error values.
-		$this->errorNum = 0;
-		$this->errorMsg = '';
+			$this->timings[] = microtime(true);
+		}
 
 		// SQLSrv_num_rows requires a static or keyset cursor.
 		if (strncmp(ltrim(strtoupper($query)), 'SELECT', strlen('SELECT')) == 0)
@@ -607,6 +611,12 @@ public function execute()
 		// Execute the query. Error suppression is used here to prevent warnings/notices that the connection has been lost.
 		$this->cursor = @sqlsrv_query($this->connection, $query, array(), $array);
 
+		if ($this->debug)
+		{
+			$this->timings[] = microtime(true);
+			$this->callStacks[] = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
+		}
+
 		// If an error occurred handle it.
 		if (!$this->cursor)
 		{
diff --git a/libraries/joomla/profiler/profiler.php b/libraries/joomla/profiler/profiler.php
index edd725dd718b6..c943272f8a335 100644
--- a/libraries/joomla/profiler/profiler.php
+++ b/libraries/joomla/profiler/profiler.php
@@ -37,6 +37,12 @@ class JProfiler
 	 */
 	protected $buffer = null;
 
+	/**
+	 * @var    array  The profiling messages.
+	 * @since  12.1
+	 */
+	protected $marks = null;
+
 	/**
 	 * @var    float
 	 * @since  12.1
@@ -64,8 +70,9 @@ class JProfiler
 	 */
 	public function __construct($prefix = '')
 	{
-		$this->start = $this->getmicrotime();
+		$this->start = microtime(1);
 		$this->prefix = $prefix;
+		$this->marks = array();
 		$this->buffer = array();
 	}
 
@@ -103,21 +110,32 @@ public static function getInstance($prefix = '')
 	 */
 	public function mark($label)
 	{
-		$current = self::getmicrotime() - $this->start;
+		$current = microtime(1) - $this->start;
 		$currentMem = memory_get_usage() / 1048576;
+
+		$m = (object) array(
+			'prefix' => $this->prefix,
+			'time' => ($current > $this->previousTime ? '+' : '-') . (($current - $this->previousTime) * 1000),
+			'totalTime' => ($current * 1000),
+			'memory' => ($currentMem > $this->previousMem ? '+' : '-') . ($currentMem - $this->previousMem),
+			'totalMemory' => $currentMem,
+			'label' => $label
+		);
+		$this->marks[] = $m;
+
 		$mark = sprintf(
-			'<code>%s %.3f seconds (+%.3f); %0.2f MB (%s%0.3f) - %s</code>',
-			$this->prefix,
-			$current,
-			$current - $this->previousTime,
-			$currentMem,
-			($currentMem > $this->previousMem) ? '+' : '', $currentMem - $this->previousMem,
-			$label
+			'%s %.3f seconds (%.3f); %0.2f MB (%0.3f) - %s',
+			$m->prefix,
+			$m->totalTime / 1000,
+			$m->time / 1000,
+			$m->totalMemory,
+			$m->memory,
+			$m->label
 		);
+		$this->buffer[] = $mark;
 
 		$this->previousTime = $current;
 		$this->previousMem = $currentMem;
-		$this->buffer[] = $mark;
 
 		return $mark;
 	}
@@ -128,6 +146,7 @@ public function mark($label)
 	 * @return  float The current time
 	 *
 	 * @since   11.1
+	 * @deprecated  12.3 (Platform) & 4.0 (CMS) - Use PHP's microtime(1)
 	 */
 	public static function getmicrotime()
 	{
@@ -154,6 +173,19 @@ public function getMemory()
 	 * Get all profiler marks.
 	 *
 	 * Returns an array of all marks created since the Profiler object
+	 * was instantiated.  Marks are objects as per {@link JProfiler::mark()}.
+	 *
+	 * @return  array  Array of profiler marks
+	 */
+	public function getMarks()
+	{
+		return $this->marks;
+	}
+
+	/**
+	 * Get all profiler mark buffers.
+	 *
+	 * Returns an array of all mark buffers created since the Profiler object
 	 * was instantiated.  Marks are strings as per {@link JProfiler::mark()}.
 	 *
 	 * @return  array  Array of profiler marks
diff --git a/media/cms/css/debug.css b/media/cms/css/debug.css
index dfbf4e0b4411b..627b99627fb7c 100644
--- a/media/cms/css/debug.css
+++ b/media/cms/css/debug.css
@@ -12,11 +12,10 @@ div#system-debug {
 	background-color: #fff;
 	color: #000;
 	border: 1px dashed silver;
-	padding: 5px;
-	text-align: left;
+	padding: 10px;
 }
 
-#system-debug div.dbgHeader {
+#system-debug div.dbg-header {
 	background-color: #ddd;
 	border: 1px solid #eee;
 	font-size: 16px;
@@ -35,14 +34,8 @@ div#system-debug {
 	margin: 0px;
 }
 
-#system-debug a:hover,
-#system-debug a:focus,
-#system-debug a:active,
-#system-debug a:link,
-#system-debug a:visited {
-	background-color: #ddd;
-	color: #000;
-	text-decoration:none;
+#system-debug .dbg-error a h3 {
+	background-color: red;
 }
 
 #system-debug a:hover h3,
@@ -51,24 +44,24 @@ div#system-debug {
 	color: #ddd;
 	font-size: 14px;
 	cursor: pointer;
-	text-decoration:none;
+	text-decoration: none;
 }
 
-#system-debug div.dbgContainer {
+#system-debug div.dbg-container {
 	padding: 10px;
 }
 
-#system-debug span.dbgCommand {
+#system-debug span.dbg-command {
 	color: blue;
 	font-weight: bold;
 }
 
-#system-debug span.dbgTable {
+#system-debug span.dbg-table {
 	color: green;
 	font-weight: bold;
 }
 
-#system-debug b.dbgOperator {
+#system-debug b.dbg-operator {
 	color: red;
 	font-weight: bold;
 }
@@ -84,13 +77,13 @@ div#system-debug {
 
 #system-debug h4 {
 	font-size: 14px;
-	font-weight:bold;
+	font-weight: bold;
 	margin: 5px 0 0 0;
 }
 
 #system-debug h5 {
 	font-size: 13px;
-	font-weight:bold;
+	font-weight: bold;
 	margin: 5px 0 0 0;
 }
 
@@ -126,125 +119,67 @@ div#system-debug {
 	font-size: 13px;
 }
 
-
-/* Common CSS for system debug */
-
-#system-debug {
-	background-color: #fff;
-	color: #000;
-	border: 1px dashed silver;
-	padding: 10px;
-}
-
-#system-debug div.dbgHeader {
-	background-color: #ddd;
-	border: 1px solid #eee;
-	font-size: 16px;
-}
-
-#system-debug h3 {
-	margin: 0;
-}
-
-#system-debug a h3 {
-	background-color: #ddd;
-	color: #000;
-	font-size: 14px;
-	padding: 5px;
-	text-decoration: none;
-	margin: 0px;
-}
-
-#system-debug .dbgerror a h3 {
+#system-debug div.dbg-header.dbg-error {
 	background-color: red;
 }
-
-#system-debug a:hover,
-#system-debug a:focus,
-#system-debug a:active,
-#system-debug a:link,
-#system-debug a:visited {
-	background-color: #ddd;
-	color: #000;
-	text-decoration:none;
-}
-
-#system-debug a:hover h3,
-#system-debug a:focus h3 {
-	background-color: #4d4d4d;
-	color: #ddd;
-	font-size: 14px;
-	cursor: pointer;
-	text-decoration:none;
-}
-
-#system-debug div.dbgContainer {
-	padding: 10px;
-}
-
-#system-debug span.dbgCommand {
-	color: blue;
-	font-weight: bold;
-}
-
-#system-debug span.dbgTable {
-	color: green;
-	font-weight: bold;
-}
-
-#system-debug b.dbgOperator {
+#system-debug .dbg-warning {
 	color: red;
 	font-weight: bold;
+	background-color: #ffffcc !important;
 }
 
-#system-debug h1 {
-	background-color: #2c2c2c;
-	color: #fff;
-	padding: 10px;
-	margin: 0;
-	font-size: 16px;
-	line-height: 1em;
+#system-debug .accordion {
+	margin-bottom: 0;
 }
-
-#system-debug h4 {
-	font-size: 14px;
-	font-weight:bold;
+#system-debug .dbg-noprofile {
+	text-decoration: line-through;
 }
 
-#system-debug h5 {
-	font-size: 13px;
-	font-weight:bold;
-	margin-top: 5px;
+/* dbg-bars */
+#system-debug .alert,
+#system-debug .dbg-bars {
+	margin-bottom: 10px;
 }
-
-div#system-debug {
-	margin: 5px;
+#system-debug .dbg-bar-spacer {
+	float: left;
+	height: 100%;
 }
-
-#system-debug ol {
-	margin-left: 25px;
-	margin-right: 25px;
+/* dbg-bars-query */
+#system-debug .dbg-bars-query .dbg-bar {
+	opacity: 0.3;
+	height: 12px;
+	margin-top: 3px;
 }
-
-#system-debug ul {
-	list-style: none;
+#system-debug .dbg-bars-query:hover .dbg-bar {
+	opacity: 0.6;
+	height: 18px;
+	margin-top: 0;
 }
-
-#system-debug li {
-	font-size: 13px;
-	margin-bottom: 10px;
+#system-debug .dbg-bars-query .dbg-bar:hover,
+#system-debug .dbg-bars-query .dbg-bar-active,
+#system-debug .dbg-bars-query:hover .dbg-bar-active {
+	opacity: 1;
+	height: 18px;
+	margin-top: 0;
 }
 
-#system-debug code {
-	font-size: 13px;
-	text-align: left;
-	direction: ltr;
+/* dbg-query-table */
+#system-debug table.dbg-query-table {
+	margin: 0px 0px 6px;
 }
-
-#system-debug p {
-	font-size: 13px;
+#system-debug table.dbg-query-table th,
+#system-debug table.dbg-query-table td {
+	padding: 3px 8px;
 }
 
-#system-debug div.dbgHeader.dbgerror {
-	background-color: red;
+#system-debug .dbg-profile-list .label {
+	display: inline-block;
+	min-width: 60px;
+	text-align: right;
 }
+
+#system-debug .dbg-query-memory,
+#system-debug .dbg-query-rowsnumber
+{
+    margin-left: 50px;
+}
\ No newline at end of file
diff --git a/plugins/system/debug/debug.php b/plugins/system/debug/debug.php
index 1c22fd55a86bf..7873088edec98 100644
--- a/plugins/system/debug/debug.php
+++ b/plugins/system/debug/debug.php
@@ -36,6 +36,30 @@ class PlgSystemDebug extends JPlugin
 	 */
 	private $logEntries = array();
 
+	/**
+	 * Holds SHOW PROFILES of queries
+	 *
+	 * @var    array
+	 * @since  CMS 3.1.2
+	 */
+	private $sqlShowProfiles = array();
+
+	/**
+	 * Holds all SHOW PROFILE FOR QUERY n, indexed by n-1
+	 *
+	 * @var    array
+	 * @since  CMS 3.1.2
+	 */
+	private $sqlShowProfileEach = array();
+
+	/**
+	 * Holds all EXPLAIN EXTENDED for all queries
+	 *
+	 * @var    array
+	 * @since  CMS 3.1.2
+	 */
+	private $explains = array();
+
 	/**
 	 * Constructor.
 	 *
@@ -72,7 +96,7 @@ public function __construct(&$subject, $config)
 
 			foreach ($this->params->get('log_priorities', array()) as $p)
 			{
-				$const = 'JLog::'.strtoupper($p);
+				$const = 'JLog::' . strtoupper($p);
 
 				if (!defined($const))
 				{
@@ -88,6 +112,10 @@ public function __construct(&$subject, $config)
 
 			JLog::addLogger(array('logger' => 'callback', 'callback' => array($this, 'logger')), $priority, $categories, $mode);
 		}
+
+		// Prepare disconnect-handler for SQL profiling:
+		$db = JFactory::getDbo();
+		$db->addDisconnectHandler(array($this, 'mysqlDisconnectHandler'));
 	}
 
 	/**
@@ -105,6 +133,13 @@ public function onAfterDispatch()
 		{
 			JHtml::_('stylesheet', 'cms/debug.css', array(), true);
 		}
+
+		// Only if debugging is enabled for SQL queries popovers
+		if (JDEBUG && $this->isAuthorisedDisplayDebug())
+		{
+			JHtml::_('bootstrap.tooltip');
+			JHtml::_('bootstrap.popover', '.hasPopover', array('placement' => 'top'));
+		}
 	}
 
 	/**
@@ -142,7 +177,8 @@ public function __destruct()
 
 		// No debug for Safari and Chrome redirection
 		if (strstr(strtolower($_SERVER['HTTP_USER_AGENT']), 'webkit') !== false
-			&& substr($contents, 0, 50) == '<html><head><meta http-equiv="refresh" content="0;')
+			&& substr($contents, 0, 50) == '<html><head><meta http-equiv="refresh" content="0;'
+		)
 		{
 			echo $contents;
 			return;
@@ -151,46 +187,46 @@ public function __destruct()
 		// Load language
 		$this->loadLanguage();
 
-		$html = '';
+		$html = array();
 
 		// Some "mousewheel protecting" JS
-		$html .= "<script>function toggleContainer(name)
+		$html[] = "<script>function toggleContainer(name)
 		{
 			var e = document.getElementById(name);// MooTools might not be available ;)
 			e.style.display = (e.style.display == 'none') ? 'block' : 'none';
 		}</script>";
 
-		$html .= '<div id="system-debug" class="profiler">';
+		$html[] = '<div id="system-debug" class="profiler">';
 
-		$html .= '<h1>' . JText::_('PLG_DEBUG_TITLE') . '</h1>';
+		$html[] = '<h1>' . JText::_('PLG_DEBUG_TITLE') . '</h1>';
 
 		if (JDEBUG)
 		{
 			if (JError::getErrors())
 			{
-				$html .= $this->display('errors');
+				$html[] = $this->display('errors');
 			}
 
-			$html .= $this->display('session');
+			$html[] = $this->display('session');
 
 			if ($this->params->get('profile', 1))
 			{
-				$html .= $this->display('profile_information');
+				$html[] = $this->display('profile_information');
 			}
 
 			if ($this->params->get('memory', 1))
 			{
-				$html .= $this->display('memory_usage');
+				$html[] = $this->display('memory_usage');
 			}
 
 			if ($this->params->get('queries', 1))
 			{
-				$html .= $this->display('queries');
+				$html[] = $this->display('queries');
 			}
 
 			if ($this->params->get('logs', 1) && !empty($this->logEntries))
 			{
-				$html .= $this->display('logs');
+				$html[] = $this->display('logs');
 			}
 		}
 
@@ -199,23 +235,23 @@ public function __destruct()
 			if ($this->params->get('language_errorfiles', 1))
 			{
 				$languageErrors = JFactory::getLanguage()->getErrorFiles();
-				$html .= $this->display('language_files_in_error', $languageErrors);
+				$html[] = $this->display('language_files_in_error', $languageErrors);
 			}
 
 			if ($this->params->get('language_files', 1))
 			{
-				$html .= $this->display('language_files_loaded');
+				$html[] = $this->display('language_files_loaded');
 			}
 
 			if ($this->params->get('language_strings'))
 			{
-				$html .= $this->display('untranslated_strings');
+				$html[] = $this->display('untranslated_strings');
 			}
 		}
 
-		$html .= '</div>';
+		$html[] = '</div>';
 
-		echo str_replace('</body>', $html . '</body>', $contents);
+		echo str_replace('</body>', implode('', $html) . '</body>', $contents);
 	}
 
 	/**
@@ -270,7 +306,7 @@ protected function display($item, array $errors = array())
 
 		if (count($errors))
 		{
-			$status = ' dbgerror';
+			$status = ' dbg-error';
 		}
 
 		$fncName = 'display' . ucfirst(str_replace('_', '', $item));
@@ -282,20 +318,20 @@ protected function display($item, array $errors = array())
 
 		$html = '';
 
-		$js = "toggleContainer('dbgContainer" . $item . "');";
+		$js = "toggleContainer('dbg_container_" . $item . "');";
 
-		$class = 'dbgHeader' . $status;
+		$class = 'dbg-header' . $status;
 
-		$html .= '<div class="' . $class . '" onclick="' . $js . '"><a href="javascript:void(0);"><h3>' . $title . '</h3></a></div>';
+		$html[] = '<div class="' . $class . '" onclick="' . $js . '"><a href="javascript:void(0);"><h3>' . $title . '</h3></a></div>';
 
 		// @todo set with js.. ?
 		$style = ' style="display: none;"';
 
-		$html .= '<div ' . $style . ' class="dbgContainer" id="dbgContainer' . $item . '">';
-		$html .= $this->$fncName();
-		$html .= '</div>';
+		$html[] = '<div ' . $style . ' class="dbg-container" id="dbg_container_' . $item . '">';
+		$html[] = $this->$fncName();
+		$html[] = '</div>';
 
-		return $html;
+		return implode('', $html);
 	}
 
 	/**
@@ -318,12 +354,12 @@ protected function displaySession($key = '', $session = null, $id = 0)
 			$session = $_SESSION;
 		}
 
-		static $html = '';
+		$html = array();
 		static $id;
 
 		if (!is_array($session))
 		{
-			$html .= $key . ' &rArr;' . $session . PHP_EOL;
+			$html[] = $key . ' &rArr;' . $session . PHP_EOL;
 		}
 		else
 		{
@@ -349,20 +385,20 @@ protected function displaySession($key = '', $session = null, $id = 0)
 
 				if (!$display)
 				{
-					$js = "toggleContainer('dbgContainer_session" . $id . "');";
+					$js = "toggleContainer('dbg_container_session" . $id . '_' . $sKey . "');";
 
-					$html .= '<div class="dbgHeader" onclick="' . $js . '"><a href="javascript:void(0);"><h3>' . $sKey . '</h3></a></div>';
+					$html[] = '<div class="dbg-header" onclick="' . $js . '"><a href="javascript:void(0);"><h3>' . $sKey . '</h3></a></div>';
 
 					// @todo set with js.. ?
 					$style = ' style="display: none;"';
 
-					$html .= '<div ' . $style . ' class="dbgContainer" id="dbgContainer_session' . $id . '">';
-					$id ++;
+					$html[] = '<div ' . $style . ' class="dbg-container" id="dbg_container_session' . $id . '_' . $sKey . '">';
+					$id++;
 
 					// Recurse...
 					$this->displaySession($sKey, $entries, $id);
 
-					$html .= '</div>';
+					$html[] = '</div>';
 
 					continue;
 				}
@@ -374,14 +410,14 @@ protected function displaySession($key = '', $session = null, $id = 0)
 
 				if (is_string($entries))
 				{
-					$html .= '<code>';
-					$html .= $sKey . ' &rArr; ' . $entries . '<br />';
-					$html .= '</code>';
+					$html[] = '<code>';
+					$html[] = $sKey . ' &rArr; ' . $entries . '<br />';
+					$html[] = '</code>';
 				}
 			}
 		}
 
-		return $html;
+		return implode('', $html);
 	}
 
 	/**
@@ -393,31 +429,31 @@ protected function displaySession($key = '', $session = null, $id = 0)
 	 */
 	protected function displayErrors()
 	{
-		$html = '';
+		$html = array();
 
-		$html .= '<ol>';
+		$html[] = '<ol>';
 
 		while ($error = JError::getError(true))
 		{
 			$col = (E_WARNING == $error->get('level')) ? 'red' : 'orange';
 
-			$html .= '<li>';
-			$html .= '<b style="color: ' . $col . '">' . $error->getMessage() . '</b><br />';
+			$html[] = '<li>';
+			$html[] = '<b style="color: ' . $col . '">' . $error->getMessage() . '</b><br />';
 
 			$info = $error->get('info');
 
 			if ($info)
 			{
-				$html .= '<pre>' . print_r($info, true) . '</pre><br />';
+				$html[] = '<pre>' . print_r($info, true) . '</pre><br />';
 			}
 
-			$html .= $this->renderBacktrace($error);
-			$html .= '</li>';
+			$html[] = $this->renderBacktrace($error);
+			$html[] = '</li>';
 		}
 
-		$html .= '</ol>';
+		$html[] = '</ol>';
 
-		return $html;
+		return implode('', $html);
 	}
 
 	/**
@@ -429,14 +465,133 @@ protected function displayErrors()
 	 */
 	protected function displayProfileInformation()
 	{
-		$html = '';
+		$html = array();
+
+		$htmlMarks = array();
 
-		foreach (JProfiler::getInstance('Application')->getBuffer() as $mark)
+		$totalTime = 0;
+		$totalMem = 0;
+		$marks = array();
+		foreach (JProfiler::getInstance('Application')->getMarks() as $mark)
 		{
-			$html .= '<div>' . $mark . '</div>';
+			$totalTime += $mark->time;
+			$totalMem += $mark->memory;
+			$htmlMark = sprintf(
+				JText::_('PLG_DEBUG_TIME') . ': <span class="label label-time">%.1f&nbsp;ms</span> / <span class="label">%.1f&nbsp;ms</span>'
+				. ' ' . JText::_('PLG_DEBUG_MEMORY') . ': <span class="label label-memory">%0.3f MB</span> / <span class="label">%0.2f MB</span>'
+				. ' %s: %s',
+				$mark->time,
+				$mark->totalTime,
+				$mark->memory,
+				$mark->totalMemory,
+				$mark->prefix,
+				$mark->label
+			);
+			$marks[] = (object) array(
+				'time' => $mark->time,
+				'memory' => $mark->memory,
+				'html' => $htmlMark,
+				'tip' => $mark->label
+			);
 		}
+		$avgTime = $totalTime / count($marks);
+		$avgMem = $totalMem / count($marks);
 
-		return $html;
+		foreach ($marks as $mark)
+		{
+			if ($mark->time > $avgTime * 1.5)
+			{
+				$barClass = 'bar-danger';
+				$labelClass = 'label-important';
+			}
+			else if ($mark->time < $avgTime / 1.5)
+			{
+				$barClass = 'bar-success';
+				$labelClass = 'label-success';
+			}
+			else
+			{
+				$barClass = 'bar-warning';
+				$labelClass = 'label-warning';
+			}
+
+			if ($mark->memory > $avgMem * 1.5)
+			{
+				$barClassMem = 'bar-danger';
+				$labelClassMem = 'label-important';
+			}
+			else if ($mark->memory < $avgMem / 1.5)
+			{
+				$barClassMem = 'bar-success';
+				$labelClassMem = 'label-success';
+			}
+			else
+			{
+				$barClassMem = 'bar-warning';
+				$labelClassMem = 'label-warning';
+			}
+			$bars[] = (object) array(
+				'width' => round($mark->time / ($totalTime / 100), 4),
+				'class' => $barClass,
+				'tip' => $mark->tip
+			);
+			$barsMem[] = (object) array(
+				'width' => round($mark->memory / ($totalMem / 100), 4),
+				'class' => $barClassMem,
+				'tip' => $mark->tip
+			);
+			$htmlMarks[] = '<div>' . str_replace('label-time', $labelClass, str_replace('label-memory', $labelClassMem, $mark->html)) . '</div>';
+		}
+		$html[] = '<h4>' . JText::_('PLG_DEBUG_TIME') . '</h4>';
+		$html[] = $this->renderBars($bars, 'profile');
+		$html[] = '<h4>' . JText::_('PLG_DEBUG_MEMORY') . '</h4>';
+		$html[] = $this->renderBars($barsMem, 'profile');
+
+		$html[] = '<div class="dbg-profile-list">' . implode('', $htmlMarks) . '</div>';
+
+		$db = JFactory::getDbo();
+
+		$log = $db->getLog();
+		if ($log)
+		{
+			$timings = $db->getTimings();
+			if ($timings)
+			{
+				$totalQueryTime = 0.0;
+				$lastStart = null;
+				foreach ($timings as $k => $v)
+				{
+					if (!($k % 2))
+					{
+						$lastStart = $v;
+					}
+					else
+					{
+						$totalQueryTime += $v - $lastStart;
+					}
+				}
+				$totalQueryTime = $totalQueryTime * 1000;
+
+				if ($totalQueryTime > ($totalTime * 0.25))
+				{
+					$labelClass = 'label-important';
+				}
+				else if ($totalQueryTime < ($totalTime * 0.15))
+				{
+					$labelClass = 'label-success';
+				}
+				else
+				{
+					$labelClass = 'label-warning';
+				}
+
+				$html[] = '<br /><div>' . JText::sprintf(
+						'PLG_DEBUG_QUERIES_TIME',
+						sprintf('<span class="label ' . $labelClass . '">%.1f&nbsp;ms</span>', $totalQueryTime)
+					) . '</div>';
+			}
+		}
+		return implode('', $html);
 	}
 
 	/**
@@ -450,12 +605,8 @@ protected function displayMemoryUsage()
 	{
 		$bytes = memory_get_usage();
 
-		$html  = '<code>';
-		$html .= JHtml::_('number.bytes', $bytes);
-		$html .= ' (' . number_format($bytes) . ' Bytes)';
-		$html .= '</code>';
-
-		return $html;
+		return '<span class="label">' . JHtml::_('number.bytes', $bytes) . '</span>'
+		. ' (<span class="label">' . number_format($bytes) . ' ' . JText::_('PLG_DEBUG_BYTES') . '</span>)';
 	}
 
 	/**
@@ -467,25 +618,176 @@ protected function displayMemoryUsage()
 	 */
 	protected function displayQueries()
 	{
-		$db	= JFactory::getDbo();
+		$db = JFactory::getDbo();
 
 		$log = $db->getLog();
 
-		if ( ! $log)
+		if (!$log)
 		{
-			return;
+			return null;
 		}
 
-		$html = '';
-
-		$html .= '<h4>' . JText::sprintf('PLG_DEBUG_QUERIES_LOGGED', $db->getCount()) . '</h4>';
+		$timings = $db->getTimings();
+		$callStacks = $db->getCallStacks();
 
-		$html .= '<ol>';
+		$db->setDebug(false);
 
 		$selectQueryTypeTicker = array();
 		$otherQueryTypeTicker = array();
 
-		foreach ($log as $query)
+		$timing = array();
+		$maxtime = 0;
+
+		if (isset($timings[0]))
+		{
+			$startTime = $timings[0];
+			$endTime = $timings[count($timings) - 1];
+			$totalBargraphTime = $endTime - $startTime;
+			if ($totalBargraphTime > 0)
+			{
+
+				foreach ($log as $id => $query)
+				{
+					if (isset($timings[$id * 2 + 1]))
+					{
+						// Compute the query time: $timing[$k] = array( queryTime, timeBetweenQueries ):
+						$timing[$id] = array(($timings[$id * 2 + 1] - $timings[$id * 2]) * 1000, $id > 0 ? ($timings[$id * 2] - $timings[$id * 2 - 1]) * 1000 : 0);
+						$maxtime = max($maxtime, $timing[$id]['0']);
+					}
+				}
+			}
+		}
+		else
+		{
+			$startTime = null;
+			$totalBargraphTime = 1;
+		}
+
+		$bars = array();
+		$info = array();
+		$totalQueryTime = 0;
+		$duplicates = array();
+
+		foreach ($log as $id => $query)
+		{
+			$did = md5($query);
+			if (!isset($duplicates[$did]))
+			{
+				$duplicates[$did] = array();
+			}
+			$duplicates[$did][] = $id;
+
+			if ($timings && isset($timings[$id * 2 + 1]))
+			{
+				// Compute the query time:
+				$queryTime = ($timings[$id * 2 + 1] - $timings[$id * 2]) * 1000;
+				$totalQueryTime += $queryTime;
+
+				// Run an EXPLAIN EXTENDED query on the SQL query if possible:
+				$hasWarnings = false;
+				$hasWarningsInProfile = false;
+
+				if (isset($this->explains[$id]))
+				{
+					$explain = $this->tableToHtml($this->explains[$id], $hasWarnings);
+				}
+				else
+				{
+					$explain = JText::sprintf('PLG_DEBUG_QUERY_EXPLAIN_NOT_POSSIBLE', htmlspecialchars($query));
+				}
+
+				// Run a SHOW PROFILE query:
+				$profile = '';
+				if (in_array($db->name, array('mysqli', 'mysql')))
+				{
+					if (isset($this->sqlShowProfileEach[$id]))
+					{
+						$profileTable = $this->sqlShowProfileEach[$id];
+						$profile = $this->tableToHtml($profileTable, $hasWarningsInProfile);
+					}
+				}
+
+				$ratio = 0.5; // how heavy should the string length count: 0 - 1
+				$timeScore = $queryTime / (strlen($query) * $ratio) * 200;
+
+				// Determine color of bargraph depending on query speed and presence of warnings in EXPLAIN:
+				if ($timeScore > 10)
+				{
+					$barClass = 'bar-danger';
+					$labelClass = 'label-important';
+				}
+				else if ($hasWarnings || $timeScore > 5)
+				{
+					$barClass = 'bar-warning';
+					$labelClass = 'label-warning';
+				}
+				else
+				{
+					$barClass = 'bar-success';
+					$labelClass = 'label-success';
+				}
+
+				// Computes bargraph as follows: Position begin and end of the bar relatively to whole execution time:
+				$prevBar = ($id && isset($bars[$id - 1])) ? $bars[$id - 1] : 0;
+
+				$barPre = round($timing[$id][1] / ($totalBargraphTime * 10), 4);
+				$barWidth = round($timing[$id][0] / ($totalBargraphTime * 10), 4);
+				$minWidth = 0.3;
+				if ($barWidth < $minWidth)
+				{
+					$barPre -= ($minWidth - $barWidth);
+					if ($barPre < 0)
+					{
+						$minWidth += $barPre;
+						$barPre = 0;
+					}
+					$barWidth = $minWidth;
+				}
+
+				$bars[$id] = (object) array(
+					'class' => $barClass,
+					'width' => $barWidth,
+					'pre' => $barPre,
+					'tip' => sprintf('%.2f&nbsp;ms', $queryTime)
+				);
+				$info[$id] = (object) array(
+					'class' => $labelClass,
+					'explain' => $explain,
+					'profile' => $profile,
+					'hasWarnings' => $hasWarnings
+				);
+			}
+		}
+		// remove single queries from $duplicates
+		$total_duplicates = 0;
+		foreach ($duplicates as $did => $dups)
+		{
+			if (count($dups) < 2)
+			{
+				unset($duplicates[$did]);
+			}
+			else
+			{
+				$total_duplicates += count($dups);
+			}
+		}
+
+		// Fix first bar width
+		$minWidth = 0.3;
+		if ($bars[0]->width < $minWidth && isset($bars[1]))
+		{
+			$bars[1]->pre -= ($minWidth - $bars[0]->width);
+			if ($bars[1]->pre < 0)
+			{
+				$minWidth += $bars[1]->pre;
+				$bars[1]->pre = 0;
+			}
+			$bars[0]->width = $minWidth;
+		}
+
+		$memoryUsageNow = memory_get_usage();
+		$list = array();
+		foreach ($log as $id => $query)
 		{
 			// Start Query Type Ticker Additions
 			$fromStart = stripos($query, 'from');
@@ -531,14 +833,199 @@ protected function displayQueries()
 
 			$text = $this->highlightQuery($query);
 
-			$html .= '<li><code>' . $text . '</code></li>';
+			if ($timings && isset($timings[$id * 2 + 1]))
+			{
+				// Compute the query time:
+				$queryTime = ($timings[$id * 2 + 1] - $timings[$id * 2]) * 1000;
+
+				// Timing
+				// Formats the output for the query time with EXPLAIN query results as tooltip:
+				$htmlTiming = '<div style="margin: 0px 0 5px;"><span class="dbg-query-time">' . JText::sprintf('PLG_DEBUG_QUERY_TIME', sprintf('<span class="label ' . $info[$id]->class . '">%.2f&nbsp;ms</span>', $timing[$id]['0']));
+
+				if ($timing[$id]['1'])
+				{
+					$htmlTiming .= ' ' . JText::sprintf('PLG_DEBUG_QUERY_AFTER_LAST', sprintf('<span class="label">%.2f&nbsp;ms</span>', $timing[$id]['1']));
+				}
+
+				if (isset($callStacks[$id][0]['memory']))
+				{
+					$memoryUsed = $callStacks[$id][0]['memory'][1] - $callStacks[$id][0]['memory'][0];
+					$memoryBeforeQuery = $callStacks[$id][0]['memory'][0];
+
+					// Determine color of query memory usage:
+					if ($memoryUsed > 0.1 * $memoryUsageNow)
+					{
+						$labelClass = 'label-important';
+					}
+					elseif ($memoryUsed > 0.05 * $memoryUsageNow)
+					{
+						$labelClass = 'label-warning';
+					}
+					else
+					{
+						$labelClass = 'label-success';
+					}
+					$htmlTiming .= ' ' . '<span class="dbg-query-memory">' . JText::sprintf('PLG_DEBUG_MEMORY_USED_FOR_QUERY',
+							sprintf('<span class="label ' . $labelClass . '">%.3f&nbsp;MB</span>', $memoryUsed / 1048576),
+							sprintf('<span class="label">%.3f&nbsp;MB</span>', $memoryBeforeQuery / 1048576))
+						. '</span>';
+
+					if ($callStacks[$id][0]['memory'][2] !== null)
+					{
+						// Determine color of number or results:
+						$resultsReturned = $callStacks[$id][0]['memory'][2];
+						if ($resultsReturned > 3000)
+						{
+							$labelClass = 'label-important';
+						}
+						elseif ($resultsReturned > 1000)
+						{
+							$labelClass = 'label-warning';
+						}
+						elseif ($resultsReturned == 0)
+						{
+							$labelClass = '';
+						}
+						else
+						{
+							$labelClass = 'label-success';
+						}
+						$htmlResultsReturned = '<span class="label ' . $labelClass . '">' . (int) $resultsReturned . '</span>';
+						$htmlTiming .= ' ' . '<span class="dbg-query-rowsnumber">' . JText::sprintf('PLG_DEBUG_ROWS_RETURNED_BY_QUERY', $htmlResultsReturned) . '</span>';
+					}
+				}
+
+				$htmlTiming .= '</div>';
+
+				// Bar
+				$htmlBar = $this->renderBars($bars, 'query', $id);
+
+				// Profile Query
+				$title = JText::_('PLG_DEBUG_PROFILE');
+				if (!$info[$id]->profile)
+				{
+					$title = '<span class="dbg-noprofile">' . $title . '</span>';
+				}
+				$htmlProfile = ($info[$id]->profile ? $info[$id]->profile : JText::_('PLG_DEBUG_NO_PROFILE'));
+
+				// Backtrace/Called
+				$htmlCallStack = '';
+				if (isset($callStacks[$id]))
+				{
+					$htmlCallStackElements = array();
+					foreach ($callStacks[$id] as $functionCall)
+					{
+						if (isset($functionCall['file']) && isset($functionCall['line']) && (strpos($functionCall['file'], '/libraries/joomla/database/') === false))
+						{
+							$htmlFile = htmlspecialchars($functionCall['file']);
+							$htmlLine = htmlspecialchars($functionCall['line']);
+							$htmlCallStackElements[] = '<span class="dbg-log-called-from">' . $this->formatLink($htmlFile, $htmlLine) . '</span>';
+						}
+					}
+					$htmlCallStack = '<div class="dbg-query-table"><div>' . implode('</div><div>', $htmlCallStackElements) . '</div></div>';
+					if (!$this->linkFormat)
+					{
+						$htmlCallStack .= '<div>[<a href="http://xdebug.org/docs/all_settings#file_link_format" target="_blank">' . JText::_('PLG_DEBUG_LINK_FORMAT') . '</a>]</div>';
+					}
+				}
+
+				$htmlAccordions = JHtml::_(
+					'bootstrap.startAccordion', 'dbg_query_' . $id, array(
+						'active' => ($info[$id]->hasWarnings ? ('dbg_query_explain_' . $id) : '')
+					)
+				);
+
+				$htmlAccordions .= JHtml::_('bootstrap.addSlide', 'dbg_query_' . $id, JText::_('PLG_DEBUG_EXPLAIN'), 'dbg_query_explain_' . $id)
+					. $info[$id]->explain
+					. JHtml::_('bootstrap.endSlide');
+
+				$htmlAccordions .= JHtml::_('bootstrap.addSlide', 'dbg_query_' . $id, $title, 'dbg_query_profile_' . $id)
+					. $htmlProfile
+					. JHtml::_('bootstrap.endSlide');
+
+				if ($htmlCallStack)
+				{
+					$htmlAccordions .= JHtml::_('bootstrap.addSlide', 'dbg_query_' . $id, JText::_('PLG_DEBUG_CALL_STACK'), 'dbg_query_callstack_' . $id)
+						. $htmlCallStack
+						. JHtml::_('bootstrap.endSlide');
+				}
+				$htmlAccordions .= JHtml::_('bootstrap.endAccordion');
+
+				$did = md5($query);
+				if (isset($duplicates[$did]))
+				{
+					$dups = array();
+					foreach ($duplicates[$did] as $dup)
+					{
+						if ($dup != $id)
+						{
+							$dups[] = '<a href="#dbg-query-' . ($dup + 1) . '">#' . ($dup + 1) . '</a>';
+						}
+					}
+					$htmlQuery = '<div class="alert alert-error">' . JText::_('PLG_DEBUG_QUERY_DUPLICATES') . ': ' . implode('&nbsp; ', $dups) . '</div>'
+						. '<pre class="alert hasTooltip" title="' . JHtml::tooltipText('PLG_DEBUG_QUERY_DUPLICATES_FOUND') . '">' . $text . '</pre>';
+				}
+				else
+				{
+					$htmlQuery = '<pre>' . $text . '</pre>';
+				}
+
+				$list[] = '<a name="dbg-query-' . ($id + 1) . '"></a>'
+					. $htmlTiming
+					. $htmlBar
+					. $htmlQuery
+					. $htmlAccordions;
+			}
+			else
+			{
+				$list[] = '<pre>' . $text . '</pre>';
+			}
+		}
+
+		$totalTime = 0;
+		foreach (JProfiler::getInstance('Application')->getMarks() as $mark)
+		{
+			$totalTime += $mark->time;
+		}
+		if ($totalQueryTime > ($totalTime * 0.25))
+		{
+			$labelClass = 'label-important';
+		}
+		else if ($totalQueryTime < ($totalTime * 0.15))
+		{
+			$labelClass = 'label-success';
+		}
+		else
+		{
+			$labelClass = 'label-warning';
+		}
+
+		$html = array();
+
+		$html[] = '<h4>' . JText::sprintf('PLG_DEBUG_QUERIES_LOGGED', $db->getCount())
+			. sprintf(' <span class="label ' . $labelClass . '">%.1f&nbsp;ms</span>', ($totalQueryTime)) . '</h4><br />';
+
+		if ($total_duplicates)
+		{
+			$html[] = '<div class="alert alert-error">'
+				. '<h4>' . JText::sprintf('PLG_DEBUG_QUERY_DUPLICATES_TOTAL_NUMBER', $total_duplicates) . '</h4>';
+			foreach ($duplicates as $dups)
+			{
+				$links = array();
+				foreach ($dups as $dup)
+				{
+					$links[] = '<a href="#dbg-query-' . ($dup + 1) . '">#' . ($dup + 1) . '</a>';
+				}
+				$html[] = '<div>' . JText::sprintf('PLG_DEBUG_QUERY_DUPLICATES_NUMBER', count($links)) . ': ' . implode('&nbsp; ', $links) . '</div>';
+			}
+			$html[] = '</div>';
 		}
 
-		$html .= '</ol>';
+		$html[] = '<ol><li>' . implode('<hr /></li><li>', $list) . '<hr /></li></ol>';
 
 		if (!$this->params->get('query_types', 1))
 		{
-			return $html;
+			return implode('', $html);
 		}
 
 		// Get the totals for the query types:
@@ -546,44 +1033,222 @@ protected function displayQueries()
 		$totalOtherQueryTypes = count($otherQueryTypeTicker);
 		$totalQueryTypes = $totalSelectQueryTypes + $totalOtherQueryTypes;
 
-		$html .= '<h4>' . JText::sprintf('PLG_DEBUG_QUERY_TYPES_LOGGED', $totalQueryTypes) . '</h4>';
+		$html[] = '<h4>' . JText::sprintf('PLG_DEBUG_QUERY_TYPES_LOGGED', $totalQueryTypes) . '</h4>';
 
 		if ($totalSelectQueryTypes)
 		{
-			$html .= '<h5>' . JText::sprintf('PLG_DEBUG_SELECT_QUERIES') . '</h5>';
+			$html[] = '<h5>' . JText::_('PLG_DEBUG_SELECT_QUERIES') . '</h5>';
 
 			arsort($selectQueryTypeTicker);
 
-			$html .= '<ol>';
-
+			$list = array();
 			foreach ($selectQueryTypeTicker as $query => $occurrences)
 			{
-				$html .= '<li><code>'
-				. JText::sprintf('PLG_DEBUG_QUERY_TYPE_AND_OCCURRENCES', $this->highlightQuery($query), $occurrences)
-				. '</code></li>';
+				$list[] = '<pre>'
+					. JText::sprintf('PLG_DEBUG_QUERY_TYPE_AND_OCCURRENCES', $this->highlightQuery($query), $occurrences)
+					. '</pre>';
 			}
 
-			$html .= '</ol>';
+			$html[] = '<ol><li>' . implode('</li><li>', $list) . '</li></ol>';
 		}
 
 		if ($totalOtherQueryTypes)
 		{
-			$html .= '<h5>' . JText::sprintf('PLG_DEBUG_OTHER_QUERIES') . '</h5>';
+			$html[] = '<h5>' . JText::_('PLG_DEBUG_OTHER_QUERIES') . '</h5>';
 
 			arsort($otherQueryTypeTicker);
 
-			$html .= '<ol>';
-
+			$list = array();
 			foreach ($otherQueryTypeTicker as $query => $occurrences)
 			{
-				$html .= '<li><code>'
-				. JText::sprintf('PLG_DEBUG_QUERY_TYPE_AND_OCCURRENCES', $this->highlightQuery($query), $occurrences)
-				. '</code></li>';
+				$list[] = '<pre>'
+					. JText::sprintf('PLG_DEBUG_QUERY_TYPE_AND_OCCURRENCES', $this->highlightQuery($query), $occurrences)
+					. '</pre>';
 			}
-			$html .= '</ol>';
+			$html[] = '<ol><li>' . implode('</li><li>', $list) . '</li></ol>';
 		}
 
-		return $html;
+		return implode('', $html);
+	}
+
+	/**
+	 * @param   int     $id    Id if the bar to highlight
+	 * @param   array   $bars  Array of bar data
+	 *
+	 * @return  string
+	 *
+	 * @since   CMS 3.1.2
+	 */
+	protected function renderBars(&$bars, $class = '', $id = '')
+	{
+		$html = array();
+		foreach ($bars as $i => $bar)
+		{
+			if (isset($bar->pre) && $bar->pre)
+			{
+				$html[] = '<div class="dbg-bar-spacer" style="width:' . $bar->pre . '%;"></div>';
+			}
+			$barClass = trim('bar dbg-bar ' . (isset($bar->class) ? $bar->class : ''));
+			if ($id != '' && $i == $id)
+			{
+				$barClass .= ' dbg-bar-active';
+			}
+			$tip = '';
+			if (isset($bar->tip) && $bar->tip)
+			{
+				$barClass .= ' hasTooltip';
+				$tip = JHtml::tooltipText($bar->tip, '', 0);
+			}
+
+			$html[] = '<a class="bar dbg-bar ' . $barClass . '" title="' . $tip . '" style="width: ' . $bar->width . '%;" href="#dbg-' . $class . '-' . ($i + 1) . '"></a>';
+		}
+		return '<div class="progress dbg-bars dbg-bars-' . $class . '">' . implode('', $html) . '</div>';
+	}
+
+	/**
+	 * @param   array    $table
+	 * @param   boolean  $hasWarnings  Changes value to true if warnings are displayed, otherwise untouched
+	 *
+	 * @return  string
+	 *
+	 * @since   CMS 3.1.2
+	 */
+	protected function tableToHtml($table, &$hasWarnings)
+	{
+
+		if (!$table)
+		{
+			return null;
+		}
+
+		$html = array();
+
+		$html[] = '<table class="table table-striped dbg-query-table"><tr>';
+		foreach (array_keys($table[0]) as $k)
+		{
+			$html[] = '<th>' . htmlspecialchars($k) . '</th>';
+		}
+		$html[] = '</tr>';
+
+		$durations = array();
+		foreach ($table as $tr)
+		{
+			if (isset($tr['Duration']))
+			{
+				$durations[] = $tr['Duration'];
+			}
+		}
+		rsort($durations, SORT_NUMERIC);
+
+		foreach ($table as $tr)
+		{
+			$html[] = '<tr>';
+			foreach ($tr as $k => $td)
+			{
+				if ($td === null)
+				{
+					// Display null's as 'NULL':
+					$td = 'NULL';
+				}
+
+				// Treat special columns:
+				if ($k == 'Duration')
+				{
+					if ($td >= 0.001 && ($td == $durations[0] || (isset($durations[1]) && $td == $durations[1])))
+					{
+						// Duration column with duration value of more than 1 ms and within 2 top duration in SQL engine: Highlight warning:
+						$html[] = '<td class="dbg-warning">';
+						$hasWarnings = true;
+					}
+					else
+					{
+						$html[] = '<td>';
+					}
+					// Display duration in ms with the unit instead of seconds:
+					$html[] = sprintf('%.1f&nbsp;ms', $td * 1000);
+				}
+				elseif ($k == 'key')
+				{
+					if ($td === 'NULL')
+					{
+						// Displays query parts which don't use a key with warning:
+						$html[] = '<td><strong>' . '<span class="dbg-warning hasTooltip" title="' . JHtml::tooltipText('PLG_DEBUG_WARNING_NO_INDEX_DESC') . '">' . JText::_('PLG_DEBUG_WARNING_NO_INDEX') . '</span>' . '</strong>';
+						$hasWarnings = true;
+					}
+					else
+					{
+						$html[] = '<td><strong>' . htmlspecialchars($td) . '</strong>';
+					}
+				}
+				elseif ($k == 'Extra')
+				{
+					$htmlTd = htmlspecialchars($td);
+					// Replace spaces with nbsp for less tall tables displayed:
+					$htmlTd = preg_replace('/([^;]) /', '\1&nbsp;', $htmlTd);
+					// Displays warnings for "Using filesort":
+					$htmlTdWithWarnings = str_replace('Using&nbsp;filesort', '<span class="dbg-warning hasTooltip" title="' . JHtml::tooltipText('PLG_DEBUG_WARNING_USING_FILESORT_DESC') . '">' . JText::_('PLG_DEBUG_WARNING_USING_FILESORT') . '</span>', $htmlTd);
+					if ($htmlTdWithWarnings !== $htmlTd)
+					{
+						$hasWarnings = true;
+					}
+
+					$html[] = '<td>' . $htmlTdWithWarnings;
+				}
+				else
+				{
+					$html[] = '<td>' . htmlspecialchars($td);
+				}
+				$html[] = '</td>';
+			}
+			$html[] = '</tr>';
+		}
+		$html[] = '</table>';
+
+		return implode('', $html);
+	}
+
+	/**
+	 * Disconnect-handler for database to collect profiling and explain information
+	 *
+	 * @since   CMS 3.1.2
+	 *
+	 * @param   JDatabaseDriver $db
+	 *
+	 * @return  void
+	 */
+	public function mysqlDisconnectHandler(&$db)
+	{
+		$db->setDebug(false);
+
+		$dbVersion5037 = (strncmp($db->name, 'mysql', 5) == 0) && version_compare($db->getVersion(), '5.0.37', '>=');
+		if ($dbVersion5037)
+		{
+			// Run a SHOW PROFILE query:
+			$db->setQuery('SHOW PROFILES'); //SHOW PROFILE ALL FOR QUERY ' . (int) ($k+1));
+			$this->sqlShowProfiles = $db->loadAssocList();
+			if ($this->sqlShowProfiles)
+			{
+				foreach ($this->sqlShowProfiles as $qn)
+				{
+					$db->setQuery('SHOW PROFILE FOR QUERY ' . (int) ($qn['Query_ID']));
+					$this->sqlShowProfileEach[(int) ($qn['Query_ID'] - 1)] = $db->loadAssocList();
+				}
+			}
+		}
+
+		if (in_array($db->name, array('mysqli', 'mysql', 'postgresql')))
+		{
+			$log = $db->getLog();
+			foreach ($log as $k => $query)
+			{
+				$dbVersion56 = (strncmp($db->name, 'mysql', 5) == 0) && version_compare($db->getVersion(), '5.6', '>=');
+				if ((stripos($query, 'select') === 0) || ($dbVersion56 && ((stripos($query, 'delete') === 0) || (stripos($query, 'update') === 0))))
+				{
+					$db->setQuery('EXPLAIN ' . ($dbVersion56 ? 'EXTENDED ' : '') . $query);
+					$this->explains[$k] = $db->loadAssocList();
+				}
+			}
+		}
 	}
 
 	/**
@@ -595,27 +1260,25 @@ protected function displayQueries()
 	 */
 	protected function displayLanguageFilesInError()
 	{
-		$html = '';
-
 		$errorfiles = JFactory::getLanguage()->getErrorFiles();
 
 		if (!count($errorfiles))
 		{
-			$html .= '<p>' . JText::_('JNONE') . '</p>';
-
-			return $html;
+			return '<p>' . JText::_('JNONE') . '</p>';
 		}
 
-		$html .= '<ul>';
+		$html = array();
+
+		$html[] = '<ul>';
 
 		foreach ($errorfiles as $file => $error)
 		{
-			$html .= '<li>' . $this->formatLink($file) . str_replace($file, '', $error) . '</li>';
+			$html[] = '<li>' . $this->formatLink($file) . str_replace($file, '', $error) . '</li>';
 		}
 
-		$html .= '</ul>';
+		$html[] = '</ul>';
 
-		return $html;
+		return implode('', $html);
 	}
 
 	/**
@@ -627,29 +1290,29 @@ protected function displayLanguageFilesInError()
 	 */
 	protected function displayLanguageFilesLoaded()
 	{
-		$html = '';
+		$html = array();
 
-		$html .= '<ul>';
+		$html[] = '<ul>';
 
-		foreach (JFactory::getLanguage()->getPaths() as $files)
+		foreach (JFactory::getLanguage()->getPaths() as /* $extension => */ $files)
 		{
 			foreach ($files as $file => $status)
 			{
-				$html .= '<li>';
+				$html[] = '<li>';
 
-				$html .= ($status)
-				? JText::_('PLG_DEBUG_LANG_LOADED')
-				: JText::_('PLG_DEBUG_LANG_NOT_LOADED');
+				$html[] = ($status)
+					? JText::_('PLG_DEBUG_LANG_LOADED')
+					: JText::_('PLG_DEBUG_LANG_NOT_LOADED');
 
-				$html .= ' : ';
-				$html .= $this->formatLink($file);
-				$html .= '</li>';
+				$html[] = ' : ';
+				$html[] = $this->formatLink($file);
+				$html[] = '</li>';
 			}
 		}
 
-		$html .= '</ul>';
+		$html[] = '</ul>';
 
-		return $html;
+		return implode('', $html);
 	}
 
 	/**
@@ -661,19 +1324,15 @@ protected function displayLanguageFilesLoaded()
 	 */
 	protected function displayUntranslatedStrings()
 	{
-		$stripFirst	= $this->params->get('strip-first');
-		$stripPref	= $this->params->get('strip-prefix');
-		$stripSuff	= $this->params->get('strip-suffix');
+		$stripFirst = $this->params->get('strip-first');
+		$stripPref = $this->params->get('strip-prefix');
+		$stripSuff = $this->params->get('strip-suffix');
 
 		$orphans = JFactory::getLanguage()->getOrphans();
 
-		$html = '';
-
-		if ( ! count($orphans))
+		if (!count($orphans))
 		{
-			$html .= '<p>' . JText::_('JNONE') . '</p>';
-
-			return $html;
+			return '<p>' . JText::_('JNONE') . '</p>';
 		}
 
 		ksort($orphans, SORT_STRING);
@@ -696,9 +1355,9 @@ protected function displayUntranslatedStrings()
 
 				if (($pos = strpos($info['string'], '=')) > 0)
 				{
-					$parts	= explode('=', $info['string']);
-					$key	= $parts[0];
-					$guess	= $parts[1];
+					$parts = explode('=', $info['string']);
+					$key = $parts[0];
+					$guess = $parts[1];
 				}
 				else
 				{
@@ -736,13 +1395,14 @@ protected function displayUntranslatedStrings()
 			}
 		}
 
+		$html = array();
 		foreach ($guesses as $file => $keys)
 		{
-			$html .= "\n\n# " . ($file ? $this->formatLink($file) : JText::_('PLG_DEBUG_UNKNOWN_FILE')) . "\n\n";
-			$html .= implode("\n", $keys);
+			$html[] = "\n\n# " . ($file ? $this->formatLink($file) : JText::_('PLG_DEBUG_UNKNOWN_FILE')) . "\n\n";
+			$html[] = implode("\n", $keys);
 		}
 
-		return '<pre>' . $html . '</pre>';
+		return '<pre>' . implode('', $html) . '</pre>';
 	}
 
 	/**
@@ -764,17 +1424,17 @@ protected function highlightQuery($query)
 
 		$regex = array(
 
-		// Tables are identified by the prefix
-		'/(=)/'
-		=> '<b class="dbgOperator">$1</b>',
+			// Tables are identified by the prefix
+			'/(=)/'
+			=> '<b class="dbg-operator">$1</b>',
 
-		// All uppercase words have a special meaning
-		'/(?<!\w|>)([A-Z_]{2,})(?!\w)/x'
-		=> '<span class="dbgCommand">$1</span>',
+			// All uppercase words have a special meaning
+			'/(?<!\w|>)([A-Z_]{2,})(?!\w)/x'
+			=> '<span class="dbg-command">$1</span>',
 
-		// Tables are identified by the prefix
-		'/(' . JFactory::getDbo()->getPrefix() . '[a-z_0-9]+)/'
-		=> '<span class="dbgTable">$1</span>'
+			// Tables are identified by the prefix
+			'/(' . JFactory::getDbo()->getPrefix() . '[a-z_0-9]+)/'
+			=> '<span class="dbg-table">$1</span>'
 
 		);
 
@@ -790,9 +1450,9 @@ protected function highlightQuery($query)
 	 *
 	 * Stolen from JError to prevent it's removal.
 	 *
-	 * @param   integer  $error  The error
+	 * @param   Exception  $error  The error
 	 *
-	 * @return  string  Contents of the backtrace
+	 * @return  string     Contents of the backtrace
 	 *
 	 * @since   2.5
 	 */
@@ -800,23 +1460,23 @@ protected function renderBacktrace($error)
 	{
 		$backtrace = $error->getTrace();
 
-		$html = '';
+		$html = array();
 
 		if (is_array($backtrace))
 		{
 			$j = 1;
 
-			$html .= '<table cellpadding="0" cellspacing="0">';
+			$html[] = '<table cellpadding="0" cellspacing="0">';
 
-			$html .= '<tr>';
-			$html .= '<td colspan="3"><strong>Call stack</strong></td>';
-			$html .= '</tr>';
+			$html[] = '<tr>';
+			$html[] = '<td colspan="3"><strong>Call stack</strong></td>';
+			$html[] = '</tr>';
 
-			$html .= '<tr>';
-			$html .= '<th>#</th>';
-			$html .= '<th>Function</th>';
-			$html .= '<th>Location</th>';
-			$html .= '</tr>';
+			$html[] = '<tr>';
+			$html[] = '<th>#</th>';
+			$html[] = '<th>Function</th>';
+			$html[] = '<th>Location</th>';
+			$html[] = '</tr>';
 
 			for ($i = count($backtrace) - 1; $i >= 0; $i--)
 			{
@@ -827,28 +1487,28 @@ protected function renderBacktrace($error)
 					$link = $this->formatLink($backtrace[$i]['file'], $backtrace[$i]['line']);
 				}
 
-				$html .= '<tr>';
-				$html .= '<td>' . $j . '</td>';
+				$html[] = '<tr>';
+				$html[] = '<td>' . $j . '</td>';
 
 				if (isset($backtrace[$i]['class']))
 				{
-					$html .= '<td>' . $backtrace[$i]['class'] . $backtrace[$i]['type'] . $backtrace[$i]['function'] . '()</td>';
+					$html[] = '<td>' . $backtrace[$i]['class'] . $backtrace[$i]['type'] . $backtrace[$i]['function'] . '()</td>';
 				}
 				else
 				{
-					$html .= '<td>' . $backtrace[$i]['function'] . '()</td>';
+					$html[] = '<td>' . $backtrace[$i]['function'] . '()</td>';
 				}
 
-				$html .= '<td>' . $link . '</td>';
+				$html[] = '<td>' . $link . '</td>';
 
-				$html .= '</tr>';
+				$html[] = '</tr>';
 				$j++;
 			}
 
-			$html .= '</table>';
+			$html[] = '</table>';
 		}
 
-		return $html;
+		return implode('', $html);
 	}
 
 	/**
@@ -914,7 +1574,8 @@ protected function displayLogs()
 			JLog::WARNING => 'WARNING',
 			JLog::NOTICE => 'NOTICE',
 			JLog::INFO => 'INFO',
-			JLog::DEBUG => 'DEBUG');
+			JLog::DEBUG => 'DEBUG'
+		);
 
 		$out = array();
 
@@ -925,5 +1586,4 @@ protected function displayLogs()
 
 		return implode('<br /><br />', $out);
 	}
-
 }