I was streaming Minecraft on snapshot 21w06a, here is short clip from it.
Timestamps (also in video)
On 0:17 I build a bridge
Then I go to my another house up to 1:50 where I missed my horse and decided to rejoin my world. After that, I went to the first place where there was the bridge.
3:37 there is no bridge.
4:56 you can see last blocks I point on blocks I placed just before building the bridge
What actually happened was...:
My bridge dissappear, no ghost blocks, my previous blocks are still there.
Steps to Reproduce:
I have no clue.
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Here is today's gz log and lastest today's log

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