When assigning any key on a keyboard to either the chat or command function, sometimes but fairly often, the assigned key's character will appear in the chat window.

Essentially, when assigning the button 'T' to open chat and '#' to enter a command, it sometimes returns said character in the chat window. Example: The button 'T' is pressed once but it still shows 't' in the opened chat window. Similarly, when pressing '#' once, '/#' appears instead.

This bug occurs also in the version 1.16.4 .

As far as I know, it would not be a hardware issue concerning the keyboard because I tried it with different keyboards (various ages, types (bluetooth or cable connection, USB or PS/2)).