[themes] How to edit default dark theme for Visual Studio Code?

tldr

You can get the colors for any theme (including the builtin ones) by switching to the theme then choosing Developer > Generate Color Theme From Current Settings from the command palette.

Details

  1. Switch to the builtin theme you wish to modify by selecting Preferences: Color Theme from the command palette then choosing the theme.

  2. Get the colors for that theme by choosing Developer > Generate Color Theme From Current Settings from the command palette. Save the file with the suffix -color-theme.jsonc.
    The color-theme part will enable color picker widgets when editing the file and jsonc sets the filetype to JSON with comments.

  3. From the command palette choose Preferences: Open Settings (JSON) to open your settings.json file. Then add your desired changes to either the workbench.colorCustomizations or tokenColorCustomizations section.

    • To restrict the settings to just this theme, use an associative arrays where the key is the theme name in brackets ([]) and the value is an associative array of settings.
    • The theme name can be found in settings.json at workbench.colorTheme.

For example, the following customizes the theme listed as Dark+ (default dark) from the Color Theme list. It sets the editor background to near black and the syntax highlighting for comments to a dim gray.

// settings.json
"workbench.colorCustomizations": {
    "[Default Dark+]": {
        "editor.background": "#19191f"
    }
},
"editor.tokenColorCustomizations": {
    "[Default Dark+]": {
        "comments": "#5F6167"
    }
},