Group DMs require joining multiple times (sometimes unsuccessful)

[simfur-ritwed]

Lately several group DMs with 3-4 ships, which I have already joined and read, present the 'Join' button multiple times afterwards. In ~75% cases this works and puts me back in the DM, in ~25% of cases it spins endlessly or fails.

System: I've seen this occur on Chrome on my MacBook Pro, but it seems worse on mobile Safari on an iPhone SE.