Glass (all colours) placed at cloud level becomes invisible when viewing through the top or side of a cloud. Glass below cloud level is still visible however. And viewing the same glass through the bottom of a cloud is still visible also.
This is potentially dangerous to the player when flying since it effectively makes invisible walls/floors.
Thank you for your report!
We're already tracking this issue at MCPE-37896, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated. If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
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