Custom diacritics with GlyphData.xml?

For my idieresis, I would like to use a narrower dieresis named dieresis.narrow (fairly common practice I suppose).

So, in my GlyphData.xml, I added this line:

Now, if I generate the idieresis then no diacritic is added at all, I only get the idotless component. The glyph named “dieresis.narrow” exists in the font, though.

What am I doing wrong? Is this not possible via GlyphData.xml?

This works out of the box (with an .i or .narrow extension), you do not need to change the XML.

Oh, yes, it does work in Glyphs 1! Looks like I just found a bug in Glyphs 2 then.

Another related question:

How can I generate my Idieresis.smcp with a narrow dieresis? I tried adding a dieresis.narrow.smcp but it is not used. On the other hand, and dieresis.smcp are used automatically.

For smallcaps, only the .sc suffix is supported.
so if you have:, dieresis, dieresis.narrow, it should pick the right components in

I fixed the code so now you can use both, .sc and .smcp.

Thanks for the explanation and the code change, Georg.

Does this mean I have to use lowercase .sc names for this to work?

I just renamed all these glyphs in the font only to get the right shape for the idieresis. But now, the glyph is in a funny position in the sort order. The reason could be that the is the only .sc glyph defined in the standard GlyphData.xml. Is there a specific concept behind this?

So, there is a bug in Glyphs 2:

· Idieresis is correctly built using
· is correctly built using
· idieresis is incorrectly built using dieresis, not dieresis.narrow as it should.

Same for imacron.
Works fine in Glyphs 1.