When you enter water as a spectator, you still see as far as you can when in any mode besides spectator. In lava, there is no fog, and you can see clearly through it, unlike any other gamemode.
Steps to reproduce:
Find a water source, or place water.
go into spectator, and enter the water.
There will be fog. Do the same with lava, and it doesn't have fog.
Lava example \/ water example \/
Thank you for your report!
However, this issue has been closed as Working as Intended, due to MCPE-161105.
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