The problem can be reproduced with fellowing simple code only in release 2020a (well, only 2020a has this problem):
a = rand(100,100);
b = a.^2;
c = fft(a(:,1));
when running this code, despite no more variable is created, Matlab will take ~200kb more memory every second, and eventually dry out all memoery I have in few hours(days). It will need all those three lines in the loop to reproduce this problem somehow. 2019a does not have this problem.
Any insight regarding this?