Using calibre 7.1. linux.
When subsetting my usual fonts, the reporting little window under each of the three fonts tells me:
Code:
FFTM NOT subset; don't know how to subset; dropped
Nevertheless the subsetting process takes place.
However the downside is that I lose the display of open-type properties (like old numerotation, etc.) in the subset.
Calibre 7.1. has been installed using the linux script provided by Calibre. Maybe some fonttools software is badly installed? I have python-fonttools 4.44.3-1 installed.