diff --git a/languages/classes/LanguageAz.php b/languages/classes/LanguageAz.php
index b413ef99734..bd42a12a1f2 100644
--- a/languages/classes/LanguageAz.php
+++ b/languages/classes/LanguageAz.php
@@ -33,7 +33,7 @@ class LanguageAz extends Language {
 	 * @return mixed|string
 	 */
 	public function ucfirst( $string ) {
-		if ( $string[0] == 'i' ) {
+		if ( substr( $string, 0, 1 ) === 'i' ) {
 			return 'İ' . substr( $string, 1 );
 		}
 		return parent::ucfirst( $string );
diff --git a/languages/classes/LanguageKk.php b/languages/classes/LanguageKk.php
index 3605e8dd72c..0460a6c6bb3 100644
--- a/languages/classes/LanguageKk.php
+++ b/languages/classes/LanguageKk.php
@@ -391,7 +391,7 @@ class LanguageKk extends LanguageKk_cyrl {
 	 * @return string
 	 */
 	public function ucfirst( $string ) {
-		if ( $string[0] == 'i' ) {
+		if ( substr( $string, 0, 1 ) === 'i' ) {
 			$variant = $this->getPreferredVariant();
 			if ( $variant == 'kk-latn' || $variant == 'kk-tr' ) {
 				return 'İ' . substr( $string, 1 );