Right below the RewriteEngine On line, add:
To enforce a no-trailing-slash policy.
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)/$ /$1 [L,R=301]To enforce a trailing-slash policy:
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^(.*[^/])$ /$1/ [L,R=301]
