[XeTeX] Discretionary hyphens don't work in paragraphed footnotes

[Jonathan Kew]

On 8/10/15 09:52, David Carlisle wrote:
> On 8 October 2015 at 09:50, Philip Taylor <P.Taylor at rhul.ac.uk> wrote:
>> Hmmm, completely stymied :  not even this works ...
>
> It wouldn't be expected to really, this was asked on stackexchange initially
> and it looks almost certainly due to the interface between tex's hyphenation and
> the font libraries, that is, an issue in the engine not due to macros,
> that's why I suggested it was posted here.

Yes, it's very possible this is an engine bug. What would be most useful 
here, I think, would be a reduced (non-LaTeX!) testcase demonstrating 
the underlying incorrect behavior at the (Xe)TeX primitive level. Any 
takers?

JK