A lot of editors support TextMate compatible syntax definitions. You can use this package to install Hjson syntax highlighting support.

• Install TextMate bundles support (if it is not installed already)

  • Open Preferences/Plugins
  • Click Install JetBrains plugin...
  • Type "textmate" in the search box
  • Install "TextMate bundles support"
  • Restart IntelliJ

• Install Hjson syntax

  • clone or download this repo git clone https://github.com/hjson/textmate-hjson.git
  • Open Preferences/Editor in IntelliJ
  • Select Textmate Bundles
  • Click on + and select the textmate-hjson folder
  • Depending on your color scheme you may wish to edit the mapping on the same screen (E.g. select something like Dracula if you are using a dark scheme)

• To install a custom color scheme

  • Create a subfolder named Themes in the textmate-hjson folder
  • Download your favorite tmTheme file to the folder you just created
  • You may need to restart/re-add the Hjson bundle
  • The theme should now show up in the mappings in Textmate Bundles

Check Editor Support for a native package first (like Sublime/Atom/Visual Studio).

If your editor is not listed you may be able to install this package if it supports TextMate syntax bundles.