I’ve just released a new free YAML Viewer that runs in IntelliJ IDEA and other JetBrains IDE’s such as Android Studio.
You can open yml/yaml local files or paste YAML from the clipboard. If you have a large file, the tree navigator and the breadcrumb will help view to view only a small part of the YAML.
To run it, download the free Applet Runner plugin from JetBrains marketplace and execute the free YAML viewer located at https://www.japplis.com/tree-data-explorer/online/yaml-viewer.html.