Hi Luigi,
>>>>> luigi scarso <luigi.scarso@gmail.com> writes:
> I will check it this weekend.
Was there any progress with respect to this issue?
I have checked it but luatex and pdftex manage the split the line in different way.
For example this gives a different log
Nullam eu ante vel est convallis dignissim.0123456789} Nulla posuere.
\bye
I will look at the xetex output closely.
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