Using plasma-discover and plasma-discover-snap-backend from KDE neon dev unstable built 20170811. snapd-glib is 1.16-0+16.04+xenial+build3 It successfully shows the snap packages such as ktuberling but when I click on install it adds it to Tasks but doesn't do any installation on the terminal I see (process:1776): Snapd-CRITICAL **: snapd_client_install_stream_finish: assertion 'request->request_type == SNAPD_REQUEST_INSTALL_STREAM' failed
I'm still experiencing this exact issue with Discover built from git master in KDE Neon.
I can reproduce on neon. I cannot reproduce on ArchLinux (with master libsnapd-glib) or in kubuntu. I suggest updating the version of the library in neon to the latest stable.