To reply to a post in !GNUsocial you have to find a copy of it in your own instance. Older versions of !StatusNet pointed both the datetime URL and the conversations URL to the originating instance; I think newer !GNUsocial code has fixed that. As a workaround you can 'favorite' the notice, then it shows up under the "Popular" menu item http://eduposse.org/url/17713 Or you can do …