.css file association?
Sometimes somehow Windows file associations get lost...

Continue and you may finish with something like this

The future tool already has a very good name:
Split-XYZ

TIG I understand this. The main problem is is not 2 or 3 axes/planes, problem is Slicer is not making actual cutting.
My English is poor and may be I do not use proper words - splitting, slicing or cutting.
So I'll use word dividing.
Slicer is not dividing objects. The idea is to divide in different planes.
In the Lion illustration above every horizontal part has to be separate object. Start with whole Lion as 1 object, applying divide in Z-plane and the result is as in illustration > separate objects instead of 1 whole lion.
Is the idea clear now?

@tig said:

With appropriate settings Slicer5 will already split your solid along any 2 planes.
...

Is this possible with Slicer?
I don't think so, or I obviously miss something in Slicer settings.

I'm talking about new plugin that will work similar to "Slicer" but cutting object to smaller parts.
Cutting in 1 or 2 or 3 planes (X, Y, Z) and why not in additional "A and R-planes" like the planes in "Slicer"

"Split to plane" is OK for few splits, but what if I want to make 100 splits(cuttings) equal in height in Z-plane then each of these in Y-plane, and then in X-plane.

OK, but the idea is to make multiple cuts at once.
To convert a cube to Rubik's cube - serial cuts in different directions controlling distance between cuts (like slicer).

Mr. TIG
Is it possible to make variation of this plugin for cutting object to pieces
(For example a big object cut to pieces fitting for 3d printing) ?
May be "Slicer" workflow will be OK - cutting in X, Y, Z or any combination of the 3 axes.

Thank you!
Why not as separate extension?

TIG has such plugins i think. Go to 'PluginStore' here, filter plugins by author (TIG) and read descriptions.