I want to add a user ÇA but only for a certain sites. If I’m developing on blah.com, I’m happy to add a root certificate, but I want to choose what sites (blah.

I want to add a user ÇA but only for a certain sites. If I’m developing on blah.com, I’m happy to add a root certificate, but I want to choose what sites (blah.com, blah.de, etc) I trust that very to accept, I don’t want it doing bank.com because I don’t trust my own CA management to be infallible. Name constraints are poorly supported, and even then that again relies on me creating the root cert correctly. Browsers seem to give me the user the choice of either accepting the cert fully or not accepting it, not giving me the control. Why is that.