1.14.4, 1.15 Pre-release 6, 1.15.1, 1.15.2, 20w06a, 20w07a, 20w08a, 20w09a, 20w11a, 20w12a, 20w13a, 20w14a, 20w15a, 20w16a, 20w17a, 20w18a, 20w19a, 20w21a, 20w22a, 1.16 Pre-release 1, 1.16 Pre-release 2, 1.16 Pre-release 5, 1.16 Pre-release 6, 1.16 Pre-release 7, 1.16 Release Candidate 1, 1.16, 1.16.1, 20w27a, 20w28a, 20w29a, 20w30a, 1.16.2 Pre-release 1, 1.16.2 Release Candidate 1, 1.16.2, 1.16.4, 20w46a, 20w48a, 20w49a, 21w03a, 1.16.5
Water caves (caves that generated in ocean biomes) do not continue to generate through any other biome (beach, plains, mushroom fields, etc.) besides the ocean biomes. Instead, it gets cut on chunk borders when approaching land, making them look unnatural.
1) Create a world with cheats on and type the seed 1205330839681468733
2) Go into spectator mode f3+n (optional: give yourself night vision with /effect give @p night_vision 1000000 0 false)
3) Type the command /tp 40 36 -209
4) Press f3+g
→ These caves are stopped by chunk borders.
Water caves would expect to generate completely, even with other biomes, which used to happen before 1.14 got released.
Water caves look unnatural and get chopped by chunks when near land.
Sometimes land caves don't generate through ocean biomes, but not all caves have this issue, depending on the biome it spawns in.
Alternative example: Seed: -1196917091952301493.
/execute in minecraft:overworld run tp @s 2272.38 63.00 597.46 -1012.92 68.85