So for a while now, the inventory window seems to open randomly, even on clients, that are running minimized. This is something, that does not occur on a regular basis, sometimes it does not happen all day, sometimes it happens every few minutes, sometimes every few hours, I found absolutely no way to reproduce this on purpose as it seems to be completely random. It got worse, when I was in a TIDI heavy system, where the window would reopen across three clients every 2-3 seconds.
This does not seem to be an issue just for me, we just had a post about it in our alliance forum, where a lot of dudes reported this across all kinds of systems (linux/win7/win10).
Already reported this as a bug report (EBR-140940), but the GM seems to see this more as a corrupt cache problem.