Sounds like libxslt needs more than just a small number of fixes, and it sounds like Google could be paying someone, like you, to help provide the necessary guidance and feedback to increase the usability and capabilities of the library and evolve it for the better.
Instead Google and others just use it, and expect that any issues that come up to be immediately fixed by the one or two open source maintainers that happen to work on it in their spare time. The power imbalance must not be lost on you here...
If you wanted to dive into what [3] does, you could do so, you could then document it, or refactor it so that it is more obvious, or remove the compile time flag entirely. There is institutional knowledge everywhere...
Instead Google and others just use it, and expect that any issues that come up to be immediately fixed by the one or two open source maintainers that happen to work on it in their spare time. The power imbalance must not be lost on you here...
If you wanted to dive into what [3] does, you could do so, you could then document it, or refactor it so that it is more obvious, or remove the compile time flag entirely. There is institutional knowledge everywhere...