I'd recommend against the spinner to indicate loading user archives: https://cl.ly/1p02320w0P3r
It gives a nervous sense of awaiting completion.
In my opinion, Dat apps on Beaker will have to make the inability to connect to an infrequently available Dat archive (say, another user one is following) less annoying and feel more acceptable. Occasional synchronization should be completely tolerable in the new P2P era.