Non-ASCII cells were centred vertically in the cell while ASCII runs were
top-anchored; the cell height is the row height rounded up, so é, ñ, €,
box-drawing and similar glyphs sat lower than their neighbours (more
visibly at larger sizes and on HiDPI). Combining marks on an ASCII base
(e + U+0301, as macOS filenames use) were also dropped by the ASCII run
path; such cells are now drawn individually with their marks.