Besides being about to use Python, it looks like the R-50iA also has "Integration with Visual Studio Code". Do you know any specifics, or have any idea as to what FANUC means when they say that the R-50iA has "Integration with Visual Studio Code"?
No idea, but if I were going to place bets, my money would be on a Fanuc library of some sort that could be integrated into VSC so that Intellisense would work with the Fanuc-specific variables and function calls. Visual Components does something similar -- you add their library to your base VSC libraries, and then VSC can help you keep your function calls and variable names correct. Probably will also let you edit&save program files directly from VSC. Since VSC is free and open-source, it saves Fanuc the effort of making their own Python IDE, while letting them leverage VSC, which is popular, high-quality, and well-supported.