In the Draw guide in chapter 4 there is a heading on page 31: Background image fills.
Since it does not work from version 7.6.2.1 onwards, I have posted a bug.
https://bugs.documentfoundation.org/show_bug.cgi?id=162602
It seems that the bug is duplicated and this option will only be available for Impress.
But for some reason they have forgotten to remove this option from the Lines and Fill toolbar.
https://bugs.documentfoundation.org/show_bug.cgi?id=154875
Although it is not clear to me if it will be implemented again in Draw, I consider that the relative heading should be removed from chapter 4 until it is implemented.