Reference manual "Quick search" box, online and offline

[Samuel Lelievre]

1.

The online SageMath reference manual at

    https://doc.sagemath.org/html/en/reference/index.html

has a "Quick search" box in the left column.

It works, albeit with some JavaScript trouble:

    https://trac.sagemath.org/ticket/29576

which could take some love... Anyone with that skills?

2.

After installing from source or from binaries, one can also

browse the reference manual offline at

    file:///path/to/sage_root/local/share/doc/sage/html/en/reference/index.html

There, the "Quick search" box does not work at all.

What would it take to make it work?