tree items jumping all the time would be annoying but having the order stuck until the tree is reloaded entirely (which is something we try to avoid) or otherwise manually triggered is even worse, i think.
tbh, implementation issues aside, i’m not sure how this could work in a transparent and not annoying way. on android there’s no tree and feed fragment is a list (that is normally hidden on almost all devices) so it works better.
anyway, if someone wants to take a stab at the implementation here’s where to begin:
tt-rss uses ItemFileWriteStore. this may or may not be relevant.
i’ll think some more about this but so far i’m not really seeing it working with the way tt-rss UI is done. sorry.