diff --git a/htdocs/core/class/html.form.class.php b/htdocs/core/class/html.form.class.php
index 03751120c7b..792ed58ab2b 100644
--- a/htdocs/core/class/html.form.class.php
+++ b/htdocs/core/class/html.form.class.php
@@ -190,7 +190,12 @@ class Form
 						$morealt=' style="width: '.$cols.'"';
 						$cols='';
 					}
-					$ret.='<textarea id="'.$htmlname.'" name="'.$htmlname.'" wrap="soft" rows="'.($tmp[1]?$tmp[1]:'20').'"'.($cols?' cols="'.$cols.'"':'class="quatrevingtpercent"').$morealt.'">'.($editvalue?$editvalue:$value).'</textarea>';
+
+					$valuetoshow = ($editvalue?$editvalue:$value);
+
+					$ret.='<textarea id="'.$htmlname.'" name="'.$htmlname.'" wrap="soft" rows="'.($tmp[1]?$tmp[1]:'20').'"'.($cols?' cols="'.$cols.'"':'class="quatrevingtpercent"').$morealt.'">';
+					$ret.=dol_string_neverthesehtmltags($valuetoshow, array('textarea'));
+					$ret.='</textarea>';
 				}
 				else if ($typeofdata == 'day' || $typeofdata == 'datepicker')
 				{
diff --git a/htdocs/core/lib/functions.lib.php b/htdocs/core/lib/functions.lib.php
index e6e3a240878..92ee1e11122 100644
--- a/htdocs/core/lib/functions.lib.php
+++ b/htdocs/core/lib/functions.lib.php
@@ -5014,7 +5014,7 @@ function picto_required()
  *  @param  string	$pagecodeto      	Encoding of input/output string
  *	@return string	    				String cleaned
  *
- * 	@see	dol_escape_htmltag strip_tags
+ * 	@see	dol_escape_htmltag strip_tags dol_string_onlythesehtmltags dol_string_neverthesehtmltags
  */
 function dol_string_nohtmltag($stringtoclean,$removelinefeed=1,$pagecodeto='UTF-8')
 {
@@ -5041,6 +5041,50 @@ function dol_string_nohtmltag($stringtoclean,$removelinefeed=1,$pagecodeto='UTF-
 	return trim($temp);
 }
 
+/**
+ *	Clean a string to keep only desirable HTML tags.
+ *
+ *	@param	string	$stringtoclean		String to clean
+ *	@return string	    				String cleaned
+ *
+ * 	@see	dol_escape_htmltag strip_tags dol_string_nohtmltag dol_string_neverthesehtmltags
+ */
+function dol_string_onlythesehtmltags($stringtoclean)
+{
+	$allowed_tags = array(
+		"html", "head", "meta", "body", "b", "br", "div", "em", "font", "img", "hr", "i", "li", "link",
+		"ol", "p", "s", "section", "span", "strong", "title",
+		"table", "tr", "th", "td", "u", "ul"
+	);
+
+	$allowed_tags_string = join("><", $allowed_tags);
+	$allowed_tags_string = preg_replace('/^>/','',$allowed_tags_string);
+	$allowed_tags_string = preg_replace('/<$/','',$allowed_tags_string);
+
+	$temp = strip_tags($stringtoclean, $allowed_tags_string);
+
+	return $temp;
+}
+
+/**
+ *	Clean a string from some undesirable HTML tags.
+ *
+ *	@param	string	$stringtoclean		String to clean
+ *	@return string	    				String cleaned
+ *
+ * 	@see	dol_escape_htmltag strip_tags dol_string_nohtmltag dol_string_onlythesehtmltags
+ */
+function dol_string_neverthesehtmltags($stringtoclean, $disallowed_tags=array('textarea'))
+{
+	$temp = $stringtoclean;
+	foreach($disallowed_tags as $tagtoremove)
+	{
+		$temp = preg_replace('/<\/?'.$tagtoremove.'>/', '', $temp);
+		$temp = preg_replace('/<\/?'.$tagtoremove.'\s+[^>]*>/', '', $temp);
+	}
+	return $temp;
+}
+
 
 /**
  * Return first line of text. Cut will depends if content is HTML or not.