diff --git a/README.md b/README.md
index cf843227..567ad5bd 100644
--- a/README.md
+++ b/README.md
@@ -12,9 +12,8 @@
 * **source**      https://github.com/tecnickcom/TCPDF
 
 
-## IMPORTANT
-A new version of this library is under development at https://github.com/tecnickcom/tc-lib-pdf and as a consequence this version will not receive any additional development or support.
-This version should be considered obsolete, new projects should use the new version as soon it will become stable.
+## NOTE
+A new version of this library is under development at https://github.com/tecnickcom/tc-lib-pdf and as a consequence this library is in support only mode.
 
 
 
diff --git a/composer.json b/composer.json
index f06c7337..b5a64873 100644
--- a/composer.json
+++ b/composer.json
@@ -13,7 +13,7 @@
     ],
     "homepage": "http://www.tcpdf.org/",
     "version": "6.6.2",
-    "license": "LGPL-3.0-only",
+    "license": "LGPL-3.0-or-later",
     "authors": [
         {
             "name": "Nicola Asuni",
diff --git a/include/barcodes/qrcode.php b/include/barcodes/qrcode.php
index 322cace3..1a64a4cb 100644
--- a/include/barcodes/qrcode.php
+++ b/include/barcodes/qrcode.php
@@ -888,6 +888,7 @@ protected function getCode() {
 			if ($col >= $this->rsblocks[0]['dataLength']) {
 				$row += $this->b1;
 			}
+			$row = (int) $row;
 			$ret = $this->rsblocks[$row]['data'][$col];
 		} elseif ($this->count < $this->dataLength + $this->eccLength) {
 			$row = ($this->count - $this->dataLength) % $this->blocks;
diff --git a/include/tcpdf_fonts.php b/include/tcpdf_fonts.php
index 305bfc64..a71c84b7 100644
--- a/include/tcpdf_fonts.php
+++ b/include/tcpdf_fonts.php
@@ -1780,9 +1780,9 @@ public static function arrUTF8ToUTF16BE($unicode, $setbom=false) {
 	 */
 	public static function UTF8ArrayToUniArray($ta, $isunicode=true) {
 		if ($isunicode) {
-			return array_map(array('TCPDF_FONTS', 'unichrUnicode'), $ta);
+			return array_map(get_called_class().'::unichrUnicode', $ta);
 		}
-		return array_map(array('TCPDF_FONTS', 'unichrASCII'), $ta);
+		return array_map(get_called_class().'::unichrASCII', $ta);
 	}
 
 	/**
@@ -2002,7 +2002,7 @@ public static function UTF8StringToArray($str, $isunicode, &$currentfont) {
 		if ($isunicode) {
 			// requires PCRE unicode support turned on
 			$chars = TCPDF_STATIC::pregSplit('//','u', $str, -1, PREG_SPLIT_NO_EMPTY);
-			$carr = array_map(array('TCPDF_FONTS', 'uniord'), $chars);
+			$carr = array_map(get_called_class().'::uniord', $chars);
 		} else {
 			$chars = str_split($str);
 			$carr = array_map('ord', $chars);
diff --git a/include/tcpdf_static.php b/include/tcpdf_static.php
index 57006552..81805054 100644
--- a/include/tcpdf_static.php
+++ b/include/tcpdf_static.php
@@ -1780,7 +1780,7 @@ public static function pregSplit($pattern, $modifiers, $subject, $limit=NULL, $f
 			if ($ret === false) {
 				return array();
 			}
-			return $ret;
+			return is_array($ret) ? $ret : array();
 		}
 		// preg_split is bugged - try alternative solution
 		$ret = array();
@@ -2124,7 +2124,7 @@ public static function _freadint($f) {
 	 * Array of page formats
 	 * measures are calculated in this way: (inches * 72) or (millimeters * 72 / 25.4)
 	 * @public static
-	 * 
+	 *
      * @var array<string,float[]>
 	 */
 	public static $page_formats = array(
diff --git a/tcpdf.php b/tcpdf.php
index 667b004f..25a00d67 100644
--- a/tcpdf.php
+++ b/tcpdf.php
@@ -2461,7 +2461,7 @@ public function setLastH($h) {
 	 */
 	public function getCellHeight($fontsize, $padding=TRUE) {
 		$height = ($fontsize * $this->cell_height_ratio);
-		if ($padding) {
+		if ($padding && !empty($this->cell_padding)) {
 			$height += ($this->cell_padding['T'] + $this->cell_padding['B']);
 		}
 		return round($height, 6);
@@ -6409,7 +6409,7 @@ public function Write($h, $txt, $link='', $fill=false, $align='', $ln=false, $st
 		// calculate maximum width for a single character on string
 		$chrw = $this->GetArrStringWidth($chars, '', '', 0, true);
 		array_walk($chrw, array($this, 'getRawCharWidth'));
-		$maxchwidth = max($chrw);
+		$maxchwidth = ((is_array($chrw) || $chrw instanceof Countable) && count($chrw) > 0) ? max($chrw) : 0;
 		// get array of chars
 		$uchars = TCPDF_FONTS::UTF8ArrayToUniArray($chars, $this->isunicode);
 		// get the number of characters
@@ -6872,6 +6872,8 @@ protected function fitBlock($w, $h, $x, $y, $fitonpage=false) {
 		}
 		// resize the block to be contained on the remaining available page or column space
 		if ($fitonpage) {
+			// fallback to avoid division by zero
+			$h = $h == 0 ? 1 : $h;
 			$ratio_wh = ($w / $h);
 			if (($y + $h) > $this->PageBreakTrigger) {
 				$h = $this->PageBreakTrigger - $y;