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Same issue as dragyndance. Opening up the inventory again seems to change which items are selectable, but some items are consistently not ever selectable. I can still interact with items by dropping everything in my inventory until I get to the item I want though. Hopefully that info helps with troubleshooting.
My bug report is one that I'm not sure if I know is a bug or a mechanic I haven't solved yet. I used a levitation potion to get to the chest in the center of a large gap in the Glacial Fortress, and I didn't have permission to take anything out of the chest. Would have been a decent haul, but I had a similar thing months ago when I got to the last chest in the Flooded Caverns. just a chest I wasn't allowed to loot.
I don't clear dungeons often enough to know if it's particularly regular, but with no fix it takes me a few days to come back with the supplies to try again.