Scripting Intellisense for IntelliJ?

Hey guys! I am new to the forum. I've been a reader for quite a while and this is my first post. I would like to ask you guys, if you use any sort of intellisense. I saw a post of someone showcasing their intellisense for intelliJ, but I couldn't figure out how they did it. Does anyone of you know, how it works? The post is the following: https://nolimitscentral.com/forum/topic/25?page=3

You may have to scroll down a bit. The post is by @bestdani

Thanks in advance, have a great day!