The exposed top part of trail ruins sometimes doesn't generate at all, which could make players not noticing that there's a trail ruin below it. This can be noticed when you're locating the structure in spectator mode.
Steps to Reproduce
Find a trail ruin with the seeds and coords provided below.
Switch to spectator and see if there is a sign of trail ruins below (which there should).
Pay attention to the surroundings on the surface.
Observed Result
The exposed top part of trail ruins doesn't generate at all.
Expected Result
The exposed top part of trail ruins should always generate to note that it is a trail ruins structure below to the players.
Sample seeds and coords:
1. 7766900979542471564
Coords: 2892 74 4447
2. -7285681425203069738
Coords: -413 74 756
This bug happens most of the time, not "sometimes." The impact is that the key new world generation feature of the 1.20 update is simply inaccessible to causal players. I filled in 9 fully zoomed out maps in a survival world last year and only found 1 trail ruin. In my current world, we have explored thousands of blocks and found none naturally. I had to resort to using the /locate command in a creative mode copy of the world to find any.