I\'m redirecting a website to a subdirectory I created. The subdirectory contains an installation of WordPress and now I want to mask the subdirectory url from the website.<
If you want to remove /apt from url why do you redirect "/" to "/apt"? Try this:
RewriteRule !^apt/ /apt%{REQUEST_URI} [L,NC]
instead of
RewriteRule ^/?$ "http\:\/\/www\.mywebsite\.com/\apt" [R=301,L]
With this rewrite you should see your application in /apt folder under url www.mywebsite.com