Running XPages in Notes Client (XPiNC) the same way as XPages are run when you access them with web browser (without any local HTTP task) is a feature that I requested about 3 years ago. It finally arrived in Notes/Domino 9.
The feature can be enabled in Application Properties "Launch" tab by checking [x] Run server-based XPages applications directly on Domino server check box. The strange thing is that "Open Designated XPage" launch option must be selected for this check box to become visible. Anyone knows why? This limits the usability of this feature quite much.
I have been trying to configure my Notes client to use this new feature as instructed in help and wiki. Basically I need to create a HTTP account in Notes client Preferences. First I tried without this account, then I created the account and have been experimenting with all account settings but the result is always the same. I get this page:

OK, I'm in China now! There is no HTTP request in domlog.nsf of the server so it really takes me directly to some strange Chinese web page. I did a full virus and windows defender scan on my computer and they found nothing. I also uninstalled my Notes clients and reinstalled to a new folder. The next question is how do I know in which URL I am now?
The most unclear field in the HTTP account setup is "Server:". This is what the help says:
In attempting to honor the request to the XPages application on Domino, XPages iterates through all the Notes accounts defined in the Notes client installation until it finds an HTTP account that matches the name of the server where the application resides
The field accepts only URL starting with http:// or https://. Which host name should I use here? We have a lot of Web Site documents, does it iterate thru all of them? I figured it must be the HTTP_HostName from server doc but as said the result is the same no matter what I try.
Has someone gotten this new feature to work?
Update 1
I tried this now with an application that is on 8.5.3 server and adjusted the HTTP account to point to that server URL. Again I got a strange page, this time a different one. The page title is My_domino_server_name.com where My_domino_server_name is the Notes name of the Domino server, not the HTTP host name. If I go to this URL with a browser I get same looking page but not exactly the same.
So the problem seems to be that it uses the Notes name of the server in the URL.
Update 2
I tried to open the application on another PC where no HTTP accounts have been defined. The result is exactly the same. Looks like it's not finding the HTTP/HTTPS account.
Update 3
When the application is opening there is this text on the screen: "Loading My Application on my_domino_server...". Again my_domino_server is the Notes name of the server, not the DNS host name used for HTTP.
Update 4
I have a PMR open with IBM and they confirmed it works for them with "Server" field value http://domino_server_notes_name/ (with no dots anywhere!). Of course that can only work in intranet. At this point I refuse to believe that the feature has been implemented in such a stupid way but we'll see what is the final outcome from IBM.
- Panu