I have created a mini font to test a problem in QuarkXPress with ligatures.
The normal ligatures ‘fi’, ‘ff’ and ‘ffi’ work (see mini-font 3). But if I add my globe as ligature from ‘∑∑’ (see mini-font 4), the font cannot be installed under Windows 10. In macOS 10.14.6 is there no problem. Font created in AI 2019 and Fontself Maker 3.5.
All files are in the ZIP archive.
Mini-Font-Ligatur Win-Problem.zip (2.1 MB)