First row of inventory items disappears

I couldn't post the in-game video to the forum because it was an AVI file, so I'm posting a screenshot instead.

This inventory has two frogs and three collection shields in the top row.

I'm currently trying to breed the frogs.

As soon as they bred, the items in my inventory unexpectedly shifted and ended up in this arrangement. The other shield and sword, and the three fossils that were in the second row, are now in the first row. If you look at the scroll bar, you can see that the second row has moved to the top. And even if I scroll through the inventory, I can't find the frogs and other items that were in the first row.

Entering build mode and then switching back to live mode restored the top row that had disappeared.

I know this isn't a video, so it might be hard to understand, but this is what's happening. It occurs when I try to sell an item, put it in a storage box, breed frogs, retrieve fossils, or open a trophy box. I sincerely hope this issue gets fixed.