All the GTA 5 Scaleforms decompiled. You shouldn’t download this without knowing how to use it, as it will mean nothing to you. The functions are located in: scripts\__Packages and possibly in other places too. Note: Not all of them may work!
The .as file for the scaleform MP_BIG_MESSAGE_FREEMODE is scripts\__Packages\com\rockstargames\gtav\Multiplayer but some may be different