that's not exactly how those work (they can claim an invention if it's done during work hours, with company equipment, in the business area of operation. Might differ from state to state, but that's the gist of those contracts
i.e. your employer can require you to assign the invention to them if it's done during work hours OR with company equipment OR related to the company's business.
The full text in the California labor code is here:
There’s only a few states (CA and few others) where the employer can’t claim IP developed on your own time and equipment. The other states absolutely can.
Most indie developers are not developing IP of interest to anyone other than the indie. Without marketing and continued development the IP is of little value.
Yes if you invent the next google in your spare time you could be in trouble. For this it’s best to get funding. At the lifestyle income level, your employer doesn’t have the time or money to waste on your passive income stream.
Obviously don’t be cavalier about it, but this will just get you fired not sued.
highly depends on your employer and your relationship to them. I've heard of cases of someone getting sued due to _an open source_ they maintained, simply out of pettiness.