Certain blocks or entities donโt appear when looking through a spectating players head, or while spectating in 3rd person perspective. These include:
1.) Hostile and passive mobs (sometimes)
2.) Other players (sometimes)
3.) Water blocks
4.) Dropped items
5.) Player heads
6.) Shields on-hand
7.) Clouds
8.)Chests
9.)World Border
10.) Glass panes
11.) Arrows in blocks (sometimes)
12.) Ice
More things might be affected than are listed here
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Thank you for your report!
We're actually already tracking this issue in MC-165958 (and its related tickets), so I 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 in the future to see if the issue has already been reported.
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