I use a Full HD display. Fonts of the menu I have enlarged by using config for qt for Mathematica - file frontend.css. It is enough to put in it *{ font-size:22pt}. But how to enlarge the default toolbar? It has very tiny icons (Insert Math, Insert TeX, etc) and small fonts (Cell style). Maybe it can use qt config for Mathematica in the same file frontend.css? I'm not familiar with qt and do not know how to make it. The OS used is Linux Mint Mate 20 based on Ubuntu 20.4.