@Jeansoo Don't worry about the language; we native speakers misinterpret each other's comments all the time.
After paying close attention the past couple of days, I can say that I still get some white objects for a second or two, but only when I've looked at a lot for the first time since the last time I cleared my caches. I guess the caches store some helpful data about lots, too. But again, I'd try lowering your number of high-detail lots to see if that helps at all.
One thing I was thinking about is that you said your highest resolution is 4096 x 2304. If that's your monitor's native resolution, that's a 16:9 ratio. (2560 x 1440 is as well.) But you have your in-game resolution set to 1920 x 1200, which is a 16:10 ratio. Your computer might render the game's graphics better if you use one of the in-game options that's also 16:9. If you google your mac's native resolution, you should also get a list of lower resolutions that are supported by your monitor.