Comment 3 for bug 670758

There is a reason for updating the fonts in entire language, script and/or Unicode blocks: it allows a controlled and harmonised update of the font family. Remember that it's not only one font that needs doing this but in the next issue of the system it will be 13. By doing it in agreed blocks we can also clearly communicate what languages and scripts are supported in the font. Adding just a number of characters within a block will eventually lead to a chaotic descent of the font development.

There are also technical reasons for ensuring the updates are harmonised and controlled. More complex scripts such as Arabic and Hebrew contain intricate mark positionings in the font, all labouriously put together in VOLT. Unfortunately, when the OpenType specifications were developed (going as far back as 1995, or even further, btw) no one anticipated the advent of fonts containing a multitude of scripts, and certainly not an environment where the fonts would be updated over a period of time by a variety of people, such as in the Ubuntu project. So, all mark positionings are glyph order dependent which means that if you would add just one Latin glyph before the Arabic/Hebrew (or other) block, the entire functionality falls apart. The same goes for adding the positionings as you suggest above, if you plan to add them via GSUB/GPOS feature.

I understand that the lack of some glyphs is frustrating, and I wish we could have given you a font that contains everything imaginable - way over 100,000 glyphs in the font - right from the start. But that would have taken quite some more time, even on just one font style. So, until we have worked out a priority list for adding further language support I beg you to be patient. We're doing everything we can to make sure as much as possible is covered by the time spring comes.