Time-varying FIR filter in Matlab

Hello,

I'm trying to implement a time-varying filter in Matlab only. I have the DSP.filter toolbox that proposes a time-varying filter but with only one tap.

https://fr.mathworks.com/help/dsp/ref/dsp.firfilter-system-object.html

The main problem is that I have the coefficients I want to implement in a matrix (with the number of taps in row), but I don't know how I could do it, if there's a way without/within the toolbox to implement such a filter, depending only on the coefficients.

Also, I don't understand what it means what it says in the documentation of the object: "the filter object updates the time-varying filter once every frame".