Document the Joomla changes to the library

.gitignore

@@ -2,3 +2,4 @@ vendor/
 composer.phar
 composer.lock
 phpunit.xml
+.idea/

src/phputf8/ord.php

@@ -7,6 +7,12 @@
 /**
 * UTF-8 aware alternative to ord
 * Returns the unicode ordinal for a character
+*
+* Joomla modification - As of PHP 7.4, curly brace access has been deprecated. As a result this function has been
+* modified to use square brace syntax
+* See https://github.com/php/php-src/commit/d574df63dc375f5fc9202ce5afde23f866b6450a
+* for additional references
+*
 * @param string UTF-8 encoded character
 * @return int unicode ordinal for the character
 * @see http://www.php.net/ord

src/phputf8/utils/validation.php

@@ -37,6 +37,12 @@ function utf8_is_valid($str) {
 
     for($i = 0; $i < $len; $i++) {
 
+        /*
+         * Joomla modification - As of PHP 7.4, curly brace access has been deprecated. As a result the line below has
+         * been modified to use square brace syntax
+         * See https://github.com/php/php-src/commit/d574df63dc375f5fc9202ce5afde23f866b6450a
+         * for additional references
+         */
         $in = ord($str[$i]);
 
         if ( $mState == 0) {