So I tried to activate an AIS near the end of the fight. Right as I confirmed the activation the boss died and I got the message that I couldn't do it because the quest ended. I forget but I don't think I closed the texbox myself before the cutscene started. Either way I was unable to move or act after the cutscene ended. Thankfully I could open the menu and abandon the mission back to the lobby, where I was able to move again. However I missed out on loot. I though I'd report this just in case. Don't risk activating an AIS after the interrupt, you might not get loot.
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