I think Moin has discovered a bug in the chat system. Also, I think there is a feature suggestion in here. There is no group setting to determine which members are allowed to start DM chats with specific groups. This is especially important for automatic groups like admin and moderators who likely do not want members to start DMs with them as a group.
(Let’s leave the community-moderators group aside, and also the question of whether members should be allowed to start chat DMs with the moderators group (the answer is no, as is being discussed in Moin’s Site feedbacktopic)
Did this only change the number shown in the interface? I am asking because when I tried to create a group chat with moderators, it still does not work.
At the top, it says 5/20 members, but the error indicates there are more than 20 users. Are those other users still bots? Why do they block the creation of the chat even though they aren’t added at the end?
Did you try using a test user or your account? I am asking because you are a moderator, so when I create a chat with the moderators group, I am added to the chat along with the moderators. When you create one, the number is one less because you aren’t added twice.
I have seen the error you saw before, too. I think it was in December when there were fewer moderators. The screenshot says 19/20, and back then, bots were still included in the count.
So far, I have not been able to reproduce the “user is invalid” error elsewhere. But the issue where the count shows 4/5 members, and the user isn’t able to create the chat, also happens on my forum.
I tried using my account. I also get 5/20 on my list. I wonder if the problem is that it is also trying to include me? If it is trying to include me then that would be a bug methinks. And a new one from this topic.