Minecraft wiki entry for Development_versions, associated text: MC-236723 – The Floating Islands preset does not seem to be generating correctly.
MC-237500 – Azalea trees can generate on top of huge mushrooms, trees & bamboo.
MC-238360 – Rooted dirt cannot replace terracotta.
MC-238529 – Azalea trees can fail to generate.
MC-238530 – Hanging roots can fail to generate.
MC-238892 – Rooted dirt doesn't replace red sand.
MC-239128 – Sweet berry bushes generate extremely rare in comparison with 1.17.1.
MC-239143 – Terracotta generating into caves in eroded badlands.
MC-239237 – Azalea trees can be generated on icebergs.
MC-239474 – Autosaving now causes extreme and gameplay-impacting lag.
MC-239489 – Melons generate rarely in jungle biomes.
MC-239847 – Chunk blending occasionally produces sharp chunk border edges.
MC-241256 – Some feature configs still expect a configured feature instead of a placed feature.
MC-241278 – Azalea trees are no longer generating.
MC-241539 – Stone generates in the side of hoodoos.
MC-241566 – Mossy cobblestone boulders generate in a grid pattern in old-growth spruce taigas.
MC-241588 – Cave vines can sometimes generate hanging on water.
MC-241672 – Mobs don't panic when burning if standing on blocks placed above water.
MC-241728 – Converting world to 1.18 pre-release 2 generates new caves in too many places.
MC-241784 – Some sliders in options menu do not work properly.
MC-241933 – Spore blossoms, cave vines, and pointed dripstones generate indented into the cave surface.