Hi Christophe,

This is not a Flush Cache for the local web browser but is a server side action for the web server your user is connected and will affect all users as the service side cache is flushed.

This should not be confused with clearing the cache for the browser client.

Normally, I use this option when I have deployed new .js files on the webserver that are not downloading properly though are changed on the server.  It is being held in a server side cache.

If you have multiple web servers, you will need to direct a local web browser to each server separately to do a flush cache on each server.  This only needs to be done once by a user so no need to have every user do this.

Hope this helps.