The latest OS X beta for 1.3 is up and you will notice a paperclip icon. This is an initial implementation of XEP-0363 HTTP Upload . I am still working on updating the UI but generally speaking, if your server supports it, it should work. I have mostly tested with Prosody. I am curious to see how well it works with other servers. There are a couple of caveats at the moment:

It shows the button for all servers at the moment. I intend to hide it for servers that do not support HTTP upload. There isn’t any feedback in the event of HTTP upload failure. I will add an alert in the future. There isn’t a progress indicator. Again, this is something I intend to add in the future If your server uses HTTPs this will not work will untrusted certificates.