Fonts prohibiting installable embedding

[Marcel Fabian Krüger]

Hi Reinhard,

On Sat, Oct 02, 2021 at 10:48:17PM +0200, Reinhard Kotucha wrote:
> What one could do is to ask the author(s) of fontforge to change the
> default settings.  This would solve the problem for many freely
> available fonts.

In my opinion the current default in fontforge is the right choice.
For non-free fonts, having installable embedding enabled would be very
bad especially since the specification states that this would give the
receiver of a file with such a font embedded full all rights the creator
of the file had, which would most likely include the right to again
embed it in documents and distribute them, effectively making the font
effectively free (at least as in beer) (I neither know nor really care
how legally binding this is, but I'm pretty sure that even the
possibility of accidentally making such a statement would be seen as
rather critical by the respective authors).

Now I'm all in favor of supporting free fonts, but I think that this
should be archived by convincing people and not by tricking people.
(Especially since the entire point of the thread is that it's easy to
forget setting these bits correctly.)

Now it might be different if free fonts would really suffer from having
the wrong bits set, but I think that that is at least questionable. Most
formats embedding fonts (including TeX for almost all fonts) subset the
fonts anyway, making the "installable" flag pointless since there isn't
enough of the fonts preserved to allow installing them. Not really because
it's not allowed to embed a installable version, but because doing so
would just lead to excessively bloated files with lots of unneeded font data.

But even if we assume that a user would otherwise had a document which
allowed them to directly install a embedded free font, what do they
actually loose from not being able to install it directly? They can use
embedded information to determine the font author and version and
directly retrieve the font from official distribution channels, avoiding
both accidental and malicious font manipulations in the process.

(Yes, there is a possibility that all other channels to retrieve the
font suddenly disappear or that our user is on a lonely island and the
digital document which just happens to include a non-subsetted embedded
font is the only way they have to get the font, but I think that such
scenarios justify changing such rather sensitive default settings)

Best,
Marcel