Caves (and mineshafts) below ocean ravines are not always properly flooded
The bug
Caves (and mineshafts) below ocean ravines are not always properly flooded. Instead the water just stops at some point in midair.
Note: Updating the block is always problematic and only updates one block of water instead of all!
How to reproduce
| Seed | 6531545027671287273 |
| World type | Default |
| Coordinates | /tp @s 170.45 58.00 -634.49 151.94 -50.55 |
Example

2018-05-27, 06:50 PM
2020-10-09, 04:19 PM
2020-10-09, 04:19 PM
16
9
Block states, Chunk loading, World generation
cave, mineshaft, ravine, water, water-block
Minecraft 18w21b - 1.16.3
Minecraft 18w21b, Minecraft 1.13-pre2, Minecraft 1.13, Minecraft 18w30b, Minecraft 18w31a, Minecraft 18w32a, Minecraft 18w33a, Minecraft 1.13.1-pre1, Minecraft 1.13.1, Minecraft 1.13.2-pre1, Minecraft 1.13.2-pre2, Minecraft 1.13.2, Minecraft 18w45a, Minecraft 18w46a, Minecraft 1.14.3, Minecraft 1.14.4 Pre-Release 1, Minecraft 1.14.4 Pre-Release 3, Minecraft 1.14.4 Pre-Release 4, Minecraft 1.14.4 Pre-Release 5, Minecraft 1.14.4 Pre-Release 6, 1.14.4, 19w34a, 19w35a, 19w36a, 19w37a, 19w38b, 19w39a, 19w40a, 19w41a, 19w42a, 19w45b, 19w46b, 1.15 Pre-release 1, 1.15 Pre-Release 2, 1.15 Pre-release 3, 1.15 Pre-release 4, 1.15 Pre-release 5, 1.15 Pre-release 6, 1.15 Pre-release 7, 1.15, 1.15.1, 1.15.1 Pre-release 1, 1.15.2 Pre-Release 1, 1.15.2 Pre-release 2, 1.15.2, 20w06a, 20w07a, 20w08a, 20w09a, 20w10a, 20w11a, 20w13a, 20w13b, 20w15a, 20w17a, 20w18a, 20w19a, 20w20a, 20w20b, 20w21a, 1.16 Pre-release 2, 1.16 Pre-release 3, 1.16 Pre-release 5, 1.16 Pre-release 6, 1.16 Pre-release 7, 1.16 Pre-release 8, 1.16 Release Candidate 1, 1.16, 1.16.1, 20w28a, 20w30a, 1.16.2 Pre-release 1, 1.16.2 Release Candidate 1, 1.16.2 Release Candidate 2, 1.16.2, 1.16.3 Release Candidate 1, 1.16.3
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