I'm sorry, even with the additional information, I still don't understand what Downloads you are trying to "stop"!
I followed your steps and opened my version of MM on my computer - mine is 28.0.2.47 (Premium), which do you have? - go to the Downloads tab and see four items listed which do seem to need to be downloaded again, even though I have previously downloaded them. Is that what you are concerned by?
If so, it does seem to be a recurring problem that no-one has yet been able to resolve. But there is nothing that says you have to download these items if you don't want or need them!