Change Default settings in Sublime Text 3

After installing sublime text 3 on Linux, I cannot seem to change the default settings, for example:

 // Controls auto pairing of quotes, brackets etc
"auto_match_enabled": true,

I can't replace true to false. The file appears to be read-only.

Sublime Text 3 does not allow you to change default settings in the Settings - Default file. This is because this file gets overwritten each time the program is upgraded, losing all of your settings. To change settings, choose Preferences -> Settings - User, create an empty object if the file has no contents:

{

}

and put your settings in it, with a comma after each one except the last (basically, it should be valid JSON):

{
    "auto_match_enabled": false
}

You can copy from the default file and paste into the user file.

Sublime Text applies settings from both your Default .sublime-settings files & User .sublime-settings files. However, any settings that exist in your User settings files will override those in the Default settings files.

This applies to both Preferences.sublime-settings and any plugin-specific .sublime-settings files.

Furthermore: project, syntax, and buffer specific settings will take precedence over a general purpose .sublime-settings file. For more information see SublimeText/Docs/Settings