I never installed that certificate and had to use VPN during this time. Still some of the people have connection issues with certain sites like facebook, gmail, etc.
Some of the companies had sued government and mobile carriers for that connection issues.
In my opinion Mozilla and Google made a right decision, there is a lot of talks of how good is Kazakhstan now for doing business, the taxes are low, it's easy to get a visas for foreigner employees, and by doing this they are losing trust to themselves.
I don't think they will manage to make a fork of some of the browsers, simply because level of the our software production is kinda low, especially in goverment sector, and people will definitely not use the browser if they will attempt to make one, they will manage to use VPN and will find other ways to just use the "normal" software.