Working with data dumps often means dealing with JSON files that are tens or hundreds of megabytes in size. Attempting to format these in standard text editors often results in crashes.
The Streaming Approach
Instead of loading the entire JSON tree into memory, use streaming parsers if you are writing a script. If you are just trying to view the data, look for dedicated client-side formatters that handle heavy DOM rendering efficiently.
A good JSON formatter will minify, beautify, and validate the syntax simultaneously.