[texinfo-pretest] texinfo 4.7.90 pretest available

[Karl Berry]

    as we agreed that a double __ could be used for unicode points
    above ffff.

Oh.  I forgot that, and apparently it didn't make it into the manual.
Makes sense, though.  If you have the discussion handy, could you send
it to me (off the list)?  No biggie, otherwise I'll look it up.

So then I guess <letter>_<letter> is the way to.  How about g_t (GNU
Texinfo) for the prefix in these unfortunate cases?

Thanks,
k