The ampersands outline is broken (it extends far beyond the bounding box of the glyph) when rendered using freetype 2.2.1 with full bytecode interpreter enabled. ftstring -m 'foo &' 1 /usr/share/fonts/truetype/ttf-dejavu/DejaVuSans.ttf Shows the issue on at least two different systems.
Created attachment 8709 [details] The string renderings at the bottom of this image shows the artifact encountered.
Hinting shouldn't exactly be used at those tiny sizes, since it doesn't make sense anymore when only 1 or 2 pixels are available. In Windows for example I've seen the hinting just being turned off if you show glyphs at those tiny sizes. It should be possible to setup fontconfig/freetype as well to get that effect if you insist on displaying fonts at size 1ppem. Next to the fact that hinting at that size is useless, it's also technically almost impossible to adjust hinting for that size. Hinting instructions start acting very weird at those sizes, as they aren't meant for it (I doubt ampersand is the only glyph with problems at size 1ppem...). Hence I'd say that any effort in trying to modify the shape at that size is better put in hinting new glyphs. Marking as wontfix. Greetings Ben
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