The bug

Entities and other non-player chat message sources, like the server console, RCON, and command blocks, appear as player heads on the Select Chat Messages to report screen. In case it isn't obvious, these sources aren't players, so they should not appear as players either.

How to reproduce

1. Create a server, and join the server with two accounts
2. Run this command:

   /execute as @e[type=!player,limit=1] run say Hi there!

3. From one account, navigate to the social interactions screen, and select the icon for the other player
4. Click the "Select Chat Messages to Report" button
   The entity that said "Hi there!" appears as a player