diff --git a/scripts/build-release.js b/scripts/build-release.js
index 9cadbd7cc..040674d07 100755
--- a/scripts/build-release.js
+++ b/scripts/build-release.js
@@ -169,7 +169,7 @@ function downloadIcons(buildFolder) {
   const dir = await buildFolder();
   // eslint-disable-next-line no-console
   console.log('Created build directory', dir);
-  await compileMain();
+  await compileMain({dev: false});
   copyStaticFolder(dir);
   await downloadIcons(dir);
   await compileDefaultPlugins(path.join(dir, 'defaultPlugins'));
diff --git a/scripts/build-utils.js b/scripts/build-utils.js
index 326230206..e33175b6c 100644
--- a/scripts/build-utils.js
+++ b/scripts/build-utils.js
@@ -92,7 +92,7 @@ function compile(buildFolder, entry) {
     .catch(die);
 }
 
-async function compileMain() {
+async function compileMain({dev}) {
   const staticDir = path.resolve(__dirname, '..', 'static');
   const out = path.join(staticDir, 'main.bundle.js');
   // check if main needs to be compiled
@@ -128,7 +128,7 @@ async function compileMain() {
       platform: 'web',
       entry: path.join(staticDir, 'main.ts'),
       out,
-      dev: false,
+      dev,
       minify: false,
       sourceMap: true,
       resetCache: true,
@@ -158,8 +158,7 @@ function getVersionNumber() {
     version = [...version.split('.').slice(0, 2), buildNumber[1]].join('.');
   }
   return version;
-}
-// Asynchronously determine current mercurial revision as string or `null` in case of any error.
+} // Asynchronously determine current mercurial revision as string or `null` in case of any error.
 function genMercurialRevision() {
   return cp
     .spawn('hg', ['log', '-r', '.', '-T', '{node}'], {encoding: 'utf8'})
diff --git a/scripts/start-dev-server.js b/scripts/start-dev-server.js
index 106f911fc..b6daba04e 100644
--- a/scripts/start-dev-server.js
+++ b/scripts/start-dev-server.js
@@ -124,7 +124,7 @@ function startAssetServer(port) {
     }
     shutdownElectron = launchElectron({
       devServerURL: `http://localhost:${port}`,
-      bundleURL: `http://localhost:${port}/src/init.bundle`,
+      bundleURL: `http://localhost:${port}/src/init.bundle?dev=true&platform=web&minify=false&excludeSource=false`,
       electronURL: `http://localhost:${port}/index.dev.html`,
     });
     res.end();
@@ -246,7 +246,7 @@ function outputScreen(socket) {
   const socket = await addWebsocket(server);
   await startMetroServer(app);
   outputScreen(socket);
-  await compileMain();
+  await compileMain({dev: true});
   shutdownElectron = launchElectron({
     devServerURL: `http://localhost:${port}`,
     bundleURL: `http://localhost:${port}/src/init.bundle`,