gecko-dev/.vscode/extensions.json

{
    // See http://go.microsoft.com/fwlink/?LinkId=827846
    // for the documentation about the extensions.json format
    "recommendations": [
        // Trim only touched lines.
        "NathanRidley.autotrim",
        // ESLint support.
        "dbaeumer.vscode-eslint",
        // C/C++ language support.
        "ms-vscode.cpptools",
        // Rust language support.
        "rust-lang.rust",
        // CSS support for HTML documents.
        "ecmel.vscode-html-css",
        // IDL language support
        "mythmon.idl"
    ]
}