rubber regen seems like the client isn't getting an update, disconnect and reconnect or surprisingly right clicking with an empty hand will make it update to show its filled again.
Also seems to be a very minor client desync issue with solar helmets and batpacks on a hosted server. wearing both when it hits nighttime the EU stored will stop counting up, but unequipping either and re-equiping seems to not check if its night time client side and it'll show phantom EU gain, also reconnecting during night time will also cause this, as well as weather change. None of this was tested with any time or weather manipulation commands, just naturally occuring.