old_contents: const path = require("path");
  const express = require("express");
  const morgan = require("morgan");
  const expressStaticGzip = require("express-static-gzip");
  
  const staticDir = path.join(__dirname, "dist");
  
  const ENVs = [
    "IRENE_API_HOST",
    "IRENE_DEVICEFARM_HOST",
    "IRENE_API_SOCKET_PATH",
    "IRENE_ENABLE_REGISTRATION",
    "IRENE_REGISTRATION_LINK",
    "IRENE_SHOW_LICENSE",
    "IRENE_CRISP_WEBSITE_ID",
    "IRENE_ENABLE_HOTJAR",
    "IRENE_ENABLE_PENDO",
    "IRENE_ENABLE_CSB",
    "IRENE_ENABLE_MARKETPLACE",
    "IRENE_ENABLE_ROLLBAR",
    "ENTERPRISE",
    "WHITELABEL_ENABLED",
    "WHITELABEL_NAME",
    "WHITELABEL_LOGO",
    "WHITELABEL_THEME",
    "WHITELABEL_FAVICON",
  ];
  
  const app = express();
  function getRuntimeConfig() {
    const content = {};
    for (const env of ENVs) {
      const value = process.env[env];
      if (value) {
        content[env] = value;
      }
    }
    return JSON.stringify(content);
  }
  app.use(morgan("tiny"));
  app.get("/runtimeconfig.js", function (req, res) {
    const config = `var runtimeGlobalConfig=${getRuntimeConfig()};`;
    res.send(config);
  });
  app.use(
    expressStaticGzip(staticDir, {
      serveStatic: {
        index: ["index.html"],
      },
    })
  );
  app.use(function (req, res) { // lgtm [js/missing-rate-limiting]
    res.sendFile(path.join(staticDir, "index.html"));
  });
  app.listen(4200, function () {
    console.log("server listening on port " + 4200);
  });
  
new_contents: const path = require("path");
  const express = require("express");
  const morgan = require("morgan");
  const expressStaticGzip = require("express-static-gzip");
  
  const staticDir = path.join(__dirname, "dist");
  
  const ENVs = [
    "IRENE_API_HOST",
    "IRENE_DEVICEFARM_HOST",
    "IRENE_API_SOCKET_PATH",
    "IRENE_ENABLE_REGISTRATION",
    "IRENE_REGISTRATION_LINK",
    "IRENE_SHOW_LICENSE",
    "IRENE_CRISP_WEBSITE_ID",
    "IRENE_ENABLE_HOTJAR",
    "IRENE_ENABLE_PENDO",
    "IRENE_ENABLE_CSB",
    "IRENE_ENABLE_MARKETPLACE",
    "IRENE_ENABLE_ROLLBAR",
    "ENTERPRISE",
    "WHITELABEL_ENABLED",
    "WHITELABEL_NAME",
    "WHITELABEL_LOGO",
    "WHITELABEL_THEME",
    "WHITELABEL_FAVICON",
  ];
  
  const app = express();
  function getRuntimeConfig() {
    const content = {};
    for (const env of ENVs) {
      const value = process.env[env];
      if (value) {
        content[env] = value;
      }
    }
    return JSON.stringify(content);
  }
  app.use(morgan("tiny"));
  app.get("/runtimeconfig.js", function (req, res) {
    const config = `var runtimeGlobalConfig=${getRuntimeConfig()};`;
    res.type('application/javascript');
    res.send(config);
  });
  app.use(
    expressStaticGzip(staticDir, {
      serveStatic: {
        index: ["index.html"],
      },
    })
  );
  app.use(function (req, res) { // lgtm [js/missing-rate-limiting]
    res.sendFile(path.join(staticDir, "index.html"));
  });
  app.listen(4200, function () {
    console.log("server listening on port " + 4200);
  });
  
subject: Return mime-type for runtimeconfig.js