the same way all other laws do, passed by the legislature and signed by the governor
>>> Why wasn't I, a resident of California, asked to vote on it?
because neither the US nor the State of California is a Direct Democracy, it is a Representative Constitutional Republic
>>> Was the law buried under some legalese and just slipped past the eyes of 39 million Californians? And nobody made any noise about it?
No there have been several thousands of News reports about it, even I as a Midwestern knew about this law months ago (I think I first heard about it mid 2019), if you did not then I would recommend you update your news sources you are in some kind of Bubble or echo chamber
the same way all other laws do, passed by the legislature and signed by the governor
>>> Why wasn't I, a resident of California, asked to vote on it?
because neither the US nor the State of California is a Direct Democracy, it is a Representative Constitutional Republic
>>> Was the law buried under some legalese and just slipped past the eyes of 39 million Californians? And nobody made any noise about it?
No there have been several thousands of News reports about it, even I as a Midwestern knew about this law months ago (I think I first heard about it mid 2019), if you did not then I would recommend you update your news sources you are in some kind of Bubble or echo chamber