Tested in Unity versions:
As long we maintain any "Flow Editor" opened, the memory usage keeps going up in Unity until there is no more memory on the computer.
I have 16GB of memory. Last time, in less than an hour Unity got 10GB of memory usage.
As soon as we close it, the memory stays static for a while. Sometimes, Unity manages to clear the part of the memory usage after from 5 minutes to half an hour.