Some users has a bunch of old libs leftover from various updates.
So core140 ships only a filesystem cleanup script and run it.
https://git.ipfire.org/?p=ipfire-2.x.git;a=commit;h=69c529972aec2641f9f689915c0a29f84d457002
The version was updated because some addons are now build and linked against the new libs so you cannot install it on the old versions without the actual core system.
btw: the kernel was not updated yet. This will follow with core142…