New XAMPP security concept:

Access to the requested directory is only available from the local network.
This setting can be configured in the file “httpd-xampp.conf”.

解决办法：

打开httpd-xampp.conf(/xampp/apache/conf/extra/httpd-xampp.conf)

找到以下内容
# New XAMPP security concept
#
<LocationMatch “^/(?i:(?:xampp|security|licenses|phpmyadmin|webalizer|server-status|server-info))”>
Order deny,allow
Deny from all
Allow from ::1 127.0.0.0/8 \
fc00::/7 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 \
81.196.40.94/32
ErrorDocument 403 /error/XAMPP_FORBIDDEN.html.var
</LocationMatch>

将Deny from all这一行注释掉，即
#Deny from all
注：需要重启apache[/opt/lampp/lampp restartapache]