Chained Context not working on PC font export (Works on Mac)

I am new to FontCreator and font creation.

I have created a script font for my sister for use in her classroom at school. This is a script font that has letter substitutions for multiple letters to be used according to specific chained contexts. I used OpenType Designer to make all the letter substitution tables and coded all the chained context conditions.

Everything works great in the FontCreator app when previewing the font.
On export everything works great in multiple applications on my Mac.
None of the letter substitutions or chained contexts work on PC.

I am using default FontCreator app export settings.
I created the font from scratch and imported each glyph (i.e. I am not attempting to edit another pre-existing font file).

Any ideas on what I am doing wrong?

I have included a few screen shots to illustrate the situation including the font NOT working on PC. I’m happy to share code or font files if it helps. I appreciate the advise.

Thanks for sharing the screenshots and details—your OpenType lookups are fine. The issue is that not every program on Windows actually uses the “calt” (Contextual Alternates) feature.

Why it works on the Mac but not on the PC

  • macOS apps such as Pages and TextEdit rely on Apple’s Core Text engine, which turns on contextual alternates automatically, so your substitutions fire without any extra effort.
  • Many Windows programs only enable the basic features (like liga for standard ligatures). calt is considered “advanced,” so unless the application explicitly requests it, Windows simply ignores those lookups.

Getting “calt” to work in Microsoft Word on Windows

Word supports contextual alternates—you just have to switch them on:

  1. Select a bit of text set in your font.
  2. Press Ctrl + D (or right-click → Font) to open the Font dialog.
  3. Go to the Advanced tab → OpenType Features.
  4. Set Ligatures to All (or at least “Contextual”) and make sure Use Contextual Alternates is ticked.
  5. Click OK—your chained substitutions should now appear.

Other Windows software

  • Apps that do support “calt” automatically: Adobe InDesign, Illustrator, Photoshop, Affinity Designer/Publisher, and modern browsers (Edge, Chrome, Firefox).
  • Apps that don’t support it at all: Notepad, WordPad, most older Office viewers, and numerous other text editors.

Bottom line

From what I can see on your screenshots, your font is fine—you just need to use software that supports the calt feature, or flip the switch manually in Word. Once that setting is enabled, Windows will apply the same substitutions you see on the Mac.

Hope that clears things up!

Erwin,

Thanks very much for the reply. This explains things well. I will text the advanced options on my PC this evening along with testing the font in some of the other compatible applications you explained.

It is a relief to know I did not miss something in creating the font.

I will confirm what I find.