FOSS gamedev and creative worlds

Strange bug on my server: when using the boats mod, sometimes the entity is "duplicated" on dig. That is to say, it appears in inventory, but it's also still in the water. Two for the price of one.

I;ve seen it the other way. When you q-drop, it never leaves your inventory. It was eventually traced to a mod to make a wall on the map edge.

Known bug.

Is there a way to fix that?