I tried this and it did not work on my Mac book pro 2012 with Catalina. I eventually found a solution, believe me you will thank me after. Its called gswitch. here is the link to the GitHub repo: https://github.com/CodySchrank/gSwitch. I just had to share this. I stay in Africa and getting my fairly used Mac 2012 cost me a lot. Finding a solution is like being gifted again.