When the player is moving with Red nether brick slab in their view a red outline appeared around the slab disappeared once player stops moving

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This is related to a different project. Use one of the links below to go to the correct project.
– Minecraft: Java Edition — Windows, Mac, and Linux
– Minecraft Launcher — bugs about the Minecraft Launcher specifically
– Minecraft: Bedrock Edition — Gear VR, iOS, Android, Windows 10 (from the Windows store), Xbox One, Windows 10 Mobile, Fire TV, Nintendo Switch, and PS4
– Minecraft: Earth — AR Compatible Devices

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Bugs in the Bedrock version of the game should be reported in the Minecraft (Bedrock codebase) project (short name MCPE). The Bedrock Dedicated Server (BDS) project is only for bugs specific to the software used to build custom multiplayer servers.