Today the super nice upstream developers of LyX reached out to me (and pelle@) as the former and still part time lyx package maintainers to inform us of an ongoing discussion in http://www.lyx.org/trac/ticket/9229. The current aproach to fix this bug might result in a name change of all fonts shipped in fonts-lyx with the next LyX release.
Why is it relevant for people not using LyX?
For some historic reasons beyond my knowledge the LyX project ships a bunch of math symbol fonts converted to ttf files. From a seperate source package they moved to be part of the lyx source package and are currently delivered via the fonts-lyx package.
Over time a bunch of other packages picked this font package up as a dependency. Among them also rather popular packages like icedove, which results in a rather fancy popcon graph. Drawback as usual is that changes might have a visible impact in places where you do not expect them.
So if you've some clue about fonts, or depend on fonts-lyx in some way, you might want to follow that issue cited above and/or get in contact with the LyX developers.
If you've some spare time feel also invited to contribute to the lyx packaging in Debian. It really deserves a lot more love then what it seldomly gets today by the brave Nick Andrik, Per and myself.