Hi,
Yes, this is a known issue; see the link below. Right now, the grid visibility applies to the iterations inside the grid, not to the grid. There are cases where you'd like to selectively hide iterations (i.e. lines), but in most cases what we want is to hide the whole grid. For now, this isn't possible using grid settings.
https://github.com/orbeon/orbeon-forms/issues/597A workaround consists in putting your grid in a section, maybe using a nested section, and setting the visibility of that section, instead of the visibility of the grid. I hope this will work for you.
Alex
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