If you aim at a block underwater, and your character is above the water you won't see the outline. I'm not sure if this affects other platforms than android.
Place a block underwater.
Make a little platform above and next to the water
Make sure the block is in reach of your player, and aim at it. You won't see the outline.
My device: Samsung Galaxy Tab A 2019
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[Mod] OcelotOnesie
Meuwser_Meuwer
Thank you for your report!
We're tracking this issue in MCPE-36193, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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