diff --git a/services/adapter.ts b/services/adapter.ts
index 607f260..10d9bd9 100644
--- a/services/adapter.ts
+++ b/services/adapter.ts
@@ -34,7 +34,7 @@ export const asyncExecFile: (
 ) => Promise<string> = Bluebird.Promise.promisify(execFile);
 export const asyncStat: (path: string) => Promise<fs.Stats> = Bluebird.Promise.promisify(fs.stat);
 export const asyncUnlink: (path: string) => Promise<void> = Bluebird.Promise.promisify(fs.unlink);
-export const asyncReadFile: (path: string, options?: any) => Promise<Buffer> = Bluebird.Promise.promisify(fs.readFile);
+export const asyncReadFile: (path: string, options?: any) => Promise<Buffer | string> = Bluebird.Promise.promisify(fs.readFile);
 export const asyncWriteFile: (path: string, contents: string, options?: fs.WriteFileOptions) => Promise<void> = Bluebird.Promise.promisify(
   fs.writeFile,
 );
diff --git a/services/run-js-service b/services/run-js-service
index 8b99578..bf9e84b 100755
--- a/services/run-js-service
+++ b/services/run-js-service
@@ -1,4 +1,6 @@
-#! /bin/sh
+#!/bin/sh
 
 # :^)
-eval "$(cat /usr/bin/run-js-service | sed 's/^thirdparty_jail=.*/thirdparty_jail=off/')"
+eval "$(sed -e '/^thirdparty_jail=/s/=.*/=off/' \
+            -e '\@/var/luna/preferences/devmode_enabled@s/if /&false \&\& /' \
+            '/usr/bin/run-js-service')"
diff --git a/services/service.ts b/services/service.ts
index 06de645..b5e4757 100644
--- a/services/service.ts
+++ b/services/service.ts
@@ -99,6 +99,15 @@ async function hashFile(filePath: string, algorithm: string): Promise<string> {
   return hash.read();
 }
 
+/**
+ * Hashes a string with specified algorithm.
+ *
+ * Input should be UTF-8.
+ */
+function hashString(data: string, algorithm: string): string {
+  return createHash(algorithm).update(data, 'utf-8').digest('hex');
+}
+
 /**
  * Elevates a package by name.
  */
@@ -527,11 +536,18 @@ function runService() {
 
         // RootMyTV v1
         if (await isFile(startDevmode)) {
-          const localChecksum = await hashFile(startDevmode, 'sha256');
+          // Warn and return empty string on read error
+          const startDevmodeContents = (await asyncReadFile(startDevmode, { encoding: 'utf-8' }).catch((err) => {
+            console.warn(`reading ${startDevmode} failed: ${err.toString()}`);
+            return '';
+          })) as string;
+
+          const localChecksum = hashString(startDevmodeContents, 'sha256');
+
           if (localChecksum !== bundledStartupChecksum && updatableChecksums.indexOf(localChecksum) !== -1) {
             await copyScript(bundledStartup, startDevmode);
             messages.push(`${startDevmode} updated!`);
-          } else if (localChecksum !== bundledJumpstartChecksum && (await asyncReadFile(startDevmode)).indexOf('org.webosbrew') !== -1) {
+          } else if (localChecksum !== bundledJumpstartChecksum && startDevmodeContents.indexOf('org.webosbrew') !== -1) {
             // Show notification about mismatched startup script if contains
             // org.webosbrew string (which is not used on jumpstart.sh nor
             // official start-devmode.sh)
@@ -539,9 +555,10 @@ function runService() {
           }
         }
       } catch (err) {
+        console.log(`Startup script update failed: ${err.stack}`);
         messages = ['Startup script update failed!', ...messages, `Error: ${err.toString()}`];
         await createToast(messages.join('<br/>'), service);
-        return { returnValue: false, statusText: 'Startup script update failed.', messages };
+        return { returnValue: false, statusText: 'Startup script update failed.', stack: err.stack, messages };
       }
 
       if (messages.length) {