At this point, we do not support this feature. By documentation, the last block in a block container should always be a paragraph. In this particular case, MS Word decides to hide the last empty paragraph after nested table. If you move the caret to the position after the nested table you will see that a paragraph pops out and when you move the caret somewhere else the paragraph will become hidden.
I have logged this as a feature request to our feedback portal. Here is a link in case you would like to track this feature: Hide the last empty paragraph in table cell placed after nested table.
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