New add-on available...
JcM Header Side Navigation V1.0
Has been made in to a header module as it’s easier to keep it on the top of the display on small screens. Other than that the rest is the same as the box version.
You can also set the sub-cats display depth in admin. Other than that the rest is the same as the box version.
That’s it enjoy.
Has been tested on Phoenix V188.8.131.52 only.
Can be see working on this site