I just came across a problem on the Serif PagePlus forums. A users was trying to kern Adobe’s Minion Pro font. On checking, I see that it contains GPOS OpenType tables, but no KERN values when opened in FontCreator’s Kerning dialogue.
PagePlus doesn’t support GPOS kerning, and neither does FontCreator’s OpenType feature editor yet.
The question is, how common are fonts like Adobe’s with only GPOS kerning and no KERN table? I already found that the Linux Libertine font is the same.
LibreOffice also doesn’t support GPOS kerning as far as I can tell, and it seems that InDesign doesn’t either. Do most other applications support GPOS kerning, and is it the preferred method for some reason? Adobe are a major font foundry, but Calibri and many other fonts do contain KERN tables. It doesn’t seem like a good plan to rely on GPOS tables if only a few applications support them.