Rivers do not always generate with continuous water

Original description (pre-1.18)

When the terrain of a river biome rises above the sea level, said river biome will generate a layer of grass rather than the water that would be expected of it. While such river biomes are and have been possible since their introduction, as a river is by definition a body of water I strongly consider this to be unintentional. There also seem to be no official mojang posts on these being intentional features either.

Seed and coordinates provided in screenshot.

This could be fixed by making rivers significantly bigger, such that they will always sink down to a level below the sea level.