Why my notepad++ become like this?

Lycan Thrope

@hoi ,
Most likely because you’ve changed some color settings somewhere in the Preferences DarkMode settings or more likely you’ve changed settings in the Style Configurator settings, I’d guess the selected text color is set to red and you’ve got a dark background. We don’t know what you did, but that isn’t among any of the standard Style Configurator Theme selections, so either you downloaded one, or made changes you didn’t know you were making.

Mark Olson

This appears to be a JSON5 file. Probably it has the .json file extension, so it is highlighted with the JSON syntax highlighter, which treats unquoted keys as a syntax error. More recent versions of Notepad++ have a JSON5 syntax highlighter, available under Language->J->JSON5 from the Notepad++ main menu. If the JSON5 syntax highlighter isn’t available, you can just change the language preference to None (Normal Text).

EDIT: even in the most recent version of Notepad++, the JSON5 syntax highlighter still doesn’t properly parse unquoted keys in objects, so you should just change your Language to None (Normal Text).

You may also find the JsonTools plugin useful for working with JSON or JSON5. If you pretty-print a JSON5 file with JsonTools, it will convert it to JSON, and then the syntax highlighting will work correctly (but you won’t have unquoted keys anymore).