Using group chat the << window shows all members not just those online. I just installed Singularity Viewer (64 bit) 1.8.7 (6994) Apr 9 2018 02:54:48 (Singularity Alpha) on my new computer and this is the first time I've had this issue. I spoke about it in the SL Singularity support group but though they were helpful, there was no solution to the problem. They suggested I send in a bug report which I am doing now.
I spoke with Lucy in chat about this at the time ...and although there is a couple of debugs that could affect the OP's issue I did not feel that she would've changed these.
@OP: Lucy, I suggested in chat that you get a fresh Installer from http://alpha.singularityviewer.org/alpha/ (Delete the old one 1st if you still have it) and re-install the programme over the top of it's self. I'm thinking there was some data corruption, during download or during installation.
Did you try this ?
An uninstall and reinstall rectified the bug. Thank you for your help!
Most welcome Lucy