@Darkwing_Duckie I've done this - finished the Heart of Corruption quest before Weisshaupt. Got the dagger working again after the siege. Circle pommel of the dagger was visible on my character again too. Went back and opened all the chests and interacted with all the statues I've left for later. Continued on playing, but when I went to go do the Davrin's The Cauldron quest, the Evanuris statue at the Hossberg Wetlands (explored the area before entering The Cauldron) was not glowing. Can't interact with it. Bug rears its head again. Back to not being able to open unique chests and interact with statues. Even with the precaution of doing the Heart of Corruption, the bug will recur. But I hope it works out for your playthrough and I wasn't just being extra careful in mine.
I've been checking on threads in hopes of any updates or if someone had found a definitive fix. I've been actively avoiding companion quests that I know have unique chests at the end since some are at locations you cannot go back to after finishing them. It's really frustrating playing like this. I hope a patch will come soon and it actually addresses this issue in the patch notes.
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