compliation failure of minimal latex documents

[Phelype Oleinik]

Hi Norbert,

> But then it should **also** work with a not loaded expl3, please.

It does, yes. When building the format we check if expl3.ltx
exists, and only if it does, then expl3 is preloaded, otherwise
nothing happens (thus it doesn't break).

But Jack's installation seems to have expl3, so
collection-latexrecommended should be there and thus also
l3backend. But this doesn't seem to be the case: as I said,
it seems he has expl3 but not l3backend, which are in the
same collection.

Meanwhile nothing in the LaTeX kernel requires expl3, it
is only preloaded.

Phelype