I'll have to reproduce it to fix it. I can't seem to see the issue on my mac.
If you can reproduce it then I can do screen sharing with you to reproduce and debug it on the machine where it happens.
It could have something to do with browser settings, firewalls, browser version, OS version. I just wouldn't know where to start without reproducing it first.
If you can get access to a machine that has the issue or even let someone else that has the issue do screen sharing with me, then I could try to figure it out.