Ага, конечно, проблему можно решить, просто перестав на неё обращать внимание.
решение может быть таким
Hi
Go to Administrators/components/com_fpslideshow/admin.fpslideshow.html.php
Replace linenr: 171
$checked = JHTML::_('grid.checkedout', $row, $i );
with
$checked = JHTML::_('grid.id', $i, $row->id );
Save the file and retry it.
This should solve the problem. It did with me.
When you get the error "Notice: Undefined property: stdClass::$id in /var/www/joomla/libraries/joomla/html/html/grid.php on line 109" then you have to specify the column-name of the id-column (should has another than "id" e.g. "product_id").
Just change
JHTML::_('grid.checkedout', $row, $i)
to
JHTML::_('grid.checkedout', $row, $i, "product_id")