The fishing line appears behind certain blocks, as well as clouds, despite the line being in front of the block.
I didn't test every block, but I tested a few that I figured would also be affected.
The blocks I found that had the issue were: Stained Glass, Chests, Ice, Slime Blocks, Beds, Shulker boxes, Bells, Honey Blocks, and player heads.
Thank you for your report!
We're actually already tracking this issue in MC-168311, so I've resolved and linked 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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