The bug
When a message containing a special character (such as a line feed) is displayed within the Select Chat Messages to Report screen, its special characters are displayed without applying any special formatting.
How to reproduce
Open a world to LAN
Run the command:
/tellraw @a {"text":"Hello\nthere!"}
Spawn a creeper
Run the command:
/execute as @e[type=creeper,limit=1] run say hi!
Open the Social Interactions menu
Start a report for the creeper (MC-253497), and select the "Select Chat Messages to Report" button
Result
Instead of
Hello
there!
(or alternatively, Hello there!
) being displayed in the list of messages, the control character for a line feed is displayed.
I can confirm this behavior.
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