diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 5d2c802..f424b4b 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -31,7 +31,7 @@ before_script:
   # Install dependencies
   - apt-get install git nodejs libcurl4-gnutls-dev libicu-dev libmcrypt-dev libvpx-dev libjpeg-dev libpng-dev libxpm-dev zlib1g-dev libfreetype6-dev libxml2-dev libexpat1-dev libbz2-dev libgmp3-dev libldap2-dev unixodbc-dev libpq-dev libsqlite3-dev libaspell-dev libsnmp-dev libpcre3-dev libtidy-dev -yqq
   # Install php extensions
-  - docker-php-ext-install mbstring pdo_mysql curl json intl gd xml zip bz2 opcache
+  - docker-php-ext-install pdo_mysql curl json intl gd xml zip bz2 opcache
   # Install & enable Xdebug for code coverage reports
   - pecl install xdebug
   - docker-php-ext-enable xdebug