I have a monospace design which I’m exporting from Glyphs 3. I have the isFixedPitch parameter set to true on the font tab, but when I export the font the isFixedPitch flag in the post table is set to 0.
For now I’m using ttx and manually changing the setting, but that’s not ideal long-term.
This has been reported and may be fixed already: Try the latest beta please. Go to Glyphs > Preferences > Updates, activate both checkboxes and press the Update button.
Thanks for the update — it looks like the related issue of monospace combining accents being exported as zero-width has been fixed, but the isFixedPitch setting is still not preserved on export as of 3.0.3 (3064).
Either way it’s good to hear this is already a known issue. I will keep checking back to see when it’s resolved.