If you find the error on RVsitebuilder interface as the following;

- Blank Page Setting 

- On step Design, all the texts are highlighted.

- Overlap content

Please follow the solution to fix the issue as below

1. edit file directadmin.conf

/usr/local/directadmin/conf/directadmin.conf
check_referer=1
to
check_referer=0

If 'check_referer' doesn't exist, please add it.

check_referer=0

2.restart DirectAdmin

service directadmin restart 

or

/etc/init.d/directadmin restart

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