When you try to fill in bucket with source water located right in middle of the world border, you cannot pour water (water just disappear immediately) and the bucket just went empty when you tried to do so.
By “non-integer world border,“ I used the command like `/worldborder set 16.5` so that the border is crossing in the middle of block. rather than right between blocks. The water source acts weird at the border when it comes to using bucket.
Refer to the raw video in the attachment to see what I mean; I started with one expected result from normal water source, and then few attempts from border.
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