I personally think it is a bug. If players don't know which item have inside other player's ender chest, how mobs do?
Environment
[+] Linux KanuX 5.6.0-kali2-amd64 #1 SMP Debian 5.6.14-1kali1 (2020-05-25) x86_64 GNU/Linux
[+] openjdk 11.0.7-ea 2020-04-14
[+] OpenJDK Runtime Environment (build 11.0.7-ea+9-post-Debian-1)
[+] OpenJDK 64-Bit Server VM (build 11.0.7-ea+9-post-Debian-1, mixed mode, sharing)
Thank you for your report!
However, we are already tracking this issue, and this report is a Duplicate of MC-172239, which has been marked as Works as Intended - this is an intentional game feature. If you have a different opinion, please visit the Feedback website.
Please use the search function in the future to prevent duplicate reports.
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