If I apply this setting to the docx file generated by the jsreport report, the table is fixed and starts on the first page.
i've tried to follow these steps using the output docx of your playground, but i don't get the same result as you, the table always stays at the second page, any clue if there is another way to do it?
GIF that shows what i am doing: https://jumpshare.com/s/YfZouzTWwR03XfeRArCK