Hello there, I noticed a bug with the /help command starting from 1.13.
It doesn't show any message for aliases. /tp is a well-known alias to /teleport now, so when I do:

/help teleport

...it works.
When I type:

/help awuofhwoaf 

...it says "unknown command".
FInally if I try:
{{}}

/help tp 

...Minecraft just doesn't 'respond' in chat at all.