Interesting. What I notice is that your memory dial has three areas while mine has two.
Has far as my tests go, the main factor of high memory usage when no images are loaded are resources. If I do 1000 copies of a 800K pattern file, that corresponds to a 800KB layer, Gimp grabs an additional 800MB on startup, which is coincidentally is the memory size of 1000 such patterns.
Has far as my tests go, the main factor of high memory usage when no images are loaded are resources. If I do 1000 copies of a 800K pattern file, that corresponds to a 800KB layer, Gimp grabs an additional 800MB on startup, which is coincidentally is the memory size of 1000 such patterns.
So, I would seriously scrutinize all the add-ons (patterns and brushes (Gimp & MyPaint) are probably the more likely culprits, but check the other types as well).