Hi @Norbert_X, I’m sorry to report my VMs confirm exactly as you so accurately describe (nice GIFs!).
I can confirm the PPA taking 16.04 MATE from 1.12 to 1.16 does change it as you would like. I haven’t heard of anyone applying this PPA recently but I’m still running with it since 2016.
To give it the best shot I went snooping around dconf settings and found no magic bullets, either.