Just played a 7v7; https://replay.faforever.com/17385251
At the end I ordered all Cybran RAS SCUs to get the rapid-fab and SAM upgrade. One SCU already had the nano-repair instead of the SAM upgrade, so the window with "Choosing this enhancement will destroy the existing enhancement in this slot. Are you sure?" popped up. But regardless of clicking Yes or No... it stayed there. I think maybe an SCU died while the popup was up.