This still happens to me quite regularly. The way to MAKE it happen is to run 2 or more instances of SC simultaneously then shut down all but one. About 50-60% of times I’ve done that I end up with the background process burning up the CPU.
It also sometimes happens randomly, but just shutting down the unwanted process is all that’s needed. Don’t even need to shut SC itself down, just that unwanted process. It’s annoying but it’s nowhere near a deal-breaker.
Still running on the same PC setup as above and I DL updates as soon as I know they’re out - I always click the “new version” prompt on first start up.
Only exception was last month when I had to go back to 18.06 cos of the sound bug but all 3 versions of 18.08 have done it on me (even the one that came out yesterday).