This probably is what you are looking for:
RewriteEngine on
RewriteRule ^/?(.*)/$ /$1 [END,QSA]
In case you want to only apply this rule if a target object actually exists in the server side file system this might do:
RewriteEngine on
RewriteCond %{REQUEST_FILENAME} ^(.*)/$
RewriteCond %1 -f [OR]
RewriteCond %1 -d
RewriteRule ^ %1 [END,QSA]
In case you receive an internal server error (http status 500) using the rule above then chances are that you operate a very old version of the apache http server. You will see a definite hint to an unsupported [END]
flag in your http servers error log file in that case. You can either try to upgrade or use the older [L]
flag, it probably will work the same in this situation, though that depends a bit on your setup.
This implementation will work likewise in the http servers host configuration or inside a dynamic configuration file (".htaccess" file). Obviously the rewriting module needs to be loaded inside the http server and enabled in the http host. In case you use a dynamic configuration file you need to take care that it's interpretation is enabled at all in the host configuration and that it is located in the host's DOCUMENT_ROOT
folder.
And a general remark: you should always prefer to place such rules in the http servers host configuration instead of using dynamic configuration files (".htaccess"). Those dynamic configuration files add complexity, are often a cause of unexpected behavior, hard to debug and they really slow down the http server. They are only provided as a last option for situations where you do not have access to the real http servers host configuration (read: really cheap service providers) or for applications insisting on writing their own rules (which is an obvious security nightmare).