Writing a path in the font_face setting should work. This would be useful to use non-default fonts on portable installs.
I posted about this on the forums.
I also need this, I am currently working on a public computer where I cannot install fonts, there should be a way to include .ttf files in the font_face setting. Like a path indeed.
I hope this will be implemented soon or that there will be a package for this.
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