@nprofile1q... it's supposed to be a visual node graph popup that lists at runtime the available engine and project classes, and pressing the button of the class (e.g. AESContext, AnimatedSprite3D) loads its functions to use in the graph.
But even if I expand a few of these one by one, my RAM jumps by like +/-10MB or so, which is why I'll have to unload collapsed classes since I'm targeting low-midrange phones as a minimum for my game.
It jumps to 1.5GB because it loads all of the classes' functions - which doesn't cause any jump in RAM in a Tree-less version I previously had, so it's purely because it jumps from 896 items in the Tree (just the classes being visible) to 148K (classes + functions).