If all of the text is showing up as one line, I'd recommend opening the dialogs.json file in an editor with a json formatter. For example, you can use Sublime text, with the Pretty JSON package: https://packagecontrol.io/packages/Pretty%20JSON
But if you don't want to deal with installing and using a new editor, probably the quickest thing to do is find a web-based json parser from among the numerous ones that will pop up if you google search for "json parser" or "json formatter," like one: https://jsonformatter.org/json-parser Then upload the dialogues.json file, hit the "format JSON" button, and then download or copy it back into your editor. The result should give you something like this: 
Hopefully that helps!