When swimming, you cannot drop a stack of items at a time.

Steps to reproduce

1. Select a stack of items in the hotbar.

2. Go in water and hold ctrl + w to swim.

3. While holding ctrl to keep swimming, press q.

Expected result

You drop the stack of items.

Observed result

You drop one item.

When you are swimming (or swim flying) you cannot drop a stack of items, you have to re-press ctrl while swimming to drop a stack of items. I'm PRETTY sure it's not supposed to work like this, but I don't know. (I tried to upload a video but no matter how many times I tried it continued to exceed the file size limit)