more-cell does not have the right width (no colspan)
In SAO, long list displays a more-row (tr), containing a more-cell (td), with a more button. The more-cell is supposed to have a colspan="number_of_visible_columns", but it does not. As a result, the more-cell has the same width as the first column containing checkboxes to select each row. And the more button does not have enough space to be displayed correctly.
Apart from the visual aspect, it has an annoying consequence on list with lots of columns, when a horizontal scrollbar is displayed. If the list is scrolled horizontally, and the first column is not visible, then the list won't load more items when scrolling to the bottom of the list. Since the first column and the more button is not visible, the IntersectionObserver defined in tree.js will never detect that we have reach the bottom of the list, and won't call the callback to trigger the click on more-button.
In tree.js, in function Sao.View.tree::display(), we normally execute this line : this.tbody.find('tr.more-row > td').attr( 'colspan', visible_columns);
But since the rows are added to tbody after being rendered to minimize browser reflow, more-row does not exists when we try to add the colspan attribute.