Minecraft Bedrock 1.17.40.23 Beta:
-Flat worlds will now upgrade properly after enabling the Caves and Cliffs Experimental Toggle.
-Tropical fish will no longer lose it's color after grabbing and releasing them in a bucket.
-Trapdoors now show up in recipe books again
-Lily pads can now be placed on water deeper than one block.
-Mobs no longer jump continuously in non-full blocks.
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https://www.youtube.com/watch?v=z0_UoiyeAvI
Minecraft Bedrock 1.17.30.23 Beta:
-Campfires can now be stacked up to 64
-Skin icon is now called "Dressing Room"
-Updated grass noise to match Java Edition.
-Biome generation is now more smoother and extreme.
-Added noodle caves. Smaller and thinner caves.
-Ore generation has been changed in order to make finding ores harder
-The size of ore veins is now larger.
-Raw Iron Block and Iron ore will now mix with Granite
-Raw Copper Block and Copper will now mix with Tuff.
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https://www.youtube.com/watch?v=1Q82WdX4dvs