Server changed my chatbar

[Fysez]

I was playing Dev PlayAlex,
And I noticed they had a cool chatbar.
Only when i log into this server,
I can actually see what I type.
When I log into other servers,
The only thing i see when I open my chatbar is a small line.
When I type,
I see no letters, No chat bar, nothing.
What do I do to fix this?