Greasy Fork

Help | Replace Text

Hey, i need help to make a new script i have no idea about scripts :'D
so i was thinking about make a scripts that's automatically replace the text " :'D " with "????"
thx...
** i need the script to replace the text in facebook chat **

There are userscripts here on greasyfork and browser add-ons on chrome appstore that replace text.
Use search.

i searched but it only change the text i see not what others see :'D

Auto Text Expander for Google Chrome extension?

Create custom keyboard shortcuts to expand and replace text as you type!

thx very very very very very much ????