Steps to reproduce the issue

After Joomla installation login to Administrator and click Blog Sample data link to install sample data

Expected result

Blog Sample data is installed

Actual result

There is an error in the sample data plugins. Response is invalid.

System information (as much as possible)

PHP Built On | Windows NT 10.0 build 16299 (Windows 10) i586
Database Version | 5.7.20-log
Database Collation | utf8mb4_unicode_ci
Database Connection Collation | utf8_general_ci
PHP Version | 7.1.11
Web Server | Apache/2.4.29 (Win32) OpenSSL/1.0.2l PHP/7.1.11
WebServer to PHP Interface | apache2handler
Joomla! Version | Joomla! 4.0.0-dev Development [ Amani ] 31-March-2017 23:59 GMT
User Agent | Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0

Additional comments