Lunar Event chests appearing as invisible slots on inventory

[unborn jackal]

Hi! I don't know if this is intended since it looks weird to have, but I'll post it anyway.
So I was doing the event quests and I wanted to upgrade a Poison Sword I had laying around
I had 2 of them stacked because same enchantment and level, so I went to fuse one of them WHILE I had one of them equipped too (Guessing maybe something happened with my held item or something)

After fusing, I came back and found empty slots that (I THINK) weren't there before. They're invisible event chests with a question mark, here's a demo video of what it looks like.

I can share my savefile in case that helps!

[royal nebula]

did you pull a time travel?

cause the event is definitely not over yet

wait no

this is weird

[carmine echo]

happens sometimes after fusing or mass dismantle, is usually fixed after swapping to a different menu or reloading

[royal nebula]

yeah