in 1.12.2 my computer could run the singleplayer world i was playing without having any delay when opening chests, accessing furnaces or activating the elytra however 1.13-pre6 there is a noticeable delay and more general server type lag where the frame rate is not affected but interacting with the world is delayed

edit:
tested again in 1.13 full release and made a more clear video showing the problem/bug
and the worlds in the video are different worlds so i dont think the bug is caused by upgrading the world
https://www.youtube.com/watch?v=9y5wWDiQiTc