Also note that any nontrivial patch there will affect all fonts in rendered documents opening us to a lot of havoc, if our vendor patch makes documents being rendered different (different font weight might change pagebreaks, thus numbers of pages, manual (hardcoded) references to pages or images -- esp. things like "last page") on Ubuntu than everywhere else (Windows, OSX). Even if we would do it right, and everyone else would do it work -- the users likely would not care, if it destroys their crossplatform document fidelity (with the same major -- even minor).
Also note that any nontrivial patch there will affect all fonts in rendered documents opening us to a lot of havoc, if our vendor patch makes documents being rendered different (different font weight might change pagebreaks, thus numbers of pages, manual (hardcoded) references to pages or images -- esp. things like "last page") on Ubuntu than everywhere else (Windows, OSX). Even if we would do it right, and everyone else would do it work -- the users likely would not care, if it destroys their crossplatform document fidelity (with the same major -- even minor).