The <fo:float> object is typically used to position an image in a separate area at the beginning of a page OR to position an image to one side, with the content flowing along-side of the image.
It is an error if <fo:float> is a descendant of a flow that is not assigned to a region-body.
It is also an error if <fo:float> is a descendant of an fo:block-container that generates an absolutely positioned area.
<fo:float> cannot have an <fo:float>, <fo:footnote> or <fo:marker> as a descendant.
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