This LaTeX package extends longtable implementing cells that: merge with the one above if it has the same content, do not merge with the one above unless the ones on the left are merged, are well behaved with respect to longtable chunking on page breaks, and automatically draw the correct separation lines. The typical use case is a table spanning multiple pages that contains a list of hierarchically organized topics (hence the package name). The package depends on array, expl3, longtable, multirow, xparse, and zref-abspage.