Where can I find toolbar icons settings in Plasma6?

My icons in toolbars became bigger after upgrading to Plasma6, I need them to revert to what did they look on Plasma 5.27.10, on my 15.6" laptop those icons consume bigger space.

It’s nightmare to change every app toolbar icons size, is there any command line or config file where to set the size at least for Qt apps ?

Is it technically possible and safe to revert this change in Plasma 6?

Or, is there any hack to set all Qt apps toolbars icons’ size to 16?