Comment 51 for bug 2017573

I'm not a font expert but quoting https://github.com/canonical/Ubuntu-fonts/issues/82

> The variable font is unhinted (a standard practice), so you may see slightly different results between the new static and variable font.

so maybe that explain the difference/not respect of hinting settings with the new Ubuntu font? Though the report comments states other fonts also have the problem so it's probably not the explanation...