Steps to Reproduce:
Build a base on a realm before 1.18.30 that has at least 3 machines (bonemeal generating, 2 wood generation) Also various buildings with the usual items needed for survival. Like storage, work area, bed, small farm, a few animals and a couple of iron golems.
Update to 1.18.30
Try to return to the base
Observed Results:
Attempt to return to base... crashes the realm. Attempt to return to base through nether portal... crashes the realm. Attempt to return to base by teleporting in creative... crashes the realm. Try to fly in creative to the base... just be able to see it, observe all mobs ceasing to move and.... crashes the realm.
Expected Results:
Would be to go to the base as being able to before 1.18.30 without it crashing the realm.
On the video where I went through the nether, the original video was 7 minutes long of.... just that screen and nothing happening. Obviously I had to shorten it to upload it. And then when trying to log in after, you get the purple 'joining realm' that lasts forever until it says it can't. Do that a few times till it is up and running again, and it goes to the last saved point