expl3 package

Just after tha last update, the package xfrac was removed, and I coudn't find it any more to reinstal.

Trying to fix the problems I unistalled the package expl3 that was marked as obsolete in the "settings" program, and as a consequence of this, the package siunitx didn't worked, an so the package circuitikz that I use as below.

\usepackage[american,cuteinductors,siunitx]{circuitikz}

When I tried to reinstall the package expl3, it didn't existed any more in any of the repository sites I tryied.

I woul'd like to know if someone know were I can get that package, I heve too many works that's not working any more.

 Jether
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