How to Deploy Helperbird in a Managed Guest Session

This guide is for school IT administrators setting up shared Chromebooks that students use for exams without signing in to a personal account.

If you tried to add Helperbird under Kiosks and got "Selected app is not enabled for kiosk mode", this is the guide you need.

Why You Cannot Add Helperbird Under Kiosks

The Kiosks tab only accepts items whose manifest declares kiosk_enabled, a key that belongs to Chrome Apps rather than browser extensions. Helperbird is a standard MV3 browser extension, so the console rejects it with "Selected app is not enabled for kiosk mode". Every ordinary extension behaves the same way.

There is a narrow exception: you can attach a companion extension to a web-app kiosk from that kiosk entry's own Extensions panel. But it will not help here, because a kiosk session has no browser toolbar and no extension icons. Google's guidance for kiosk extensions states plainly that they must work without any direct user interaction with a popup or options page. Helperbird is opened from its toolbar icon and panel, so in a kiosk session a student would have no way to reach it.

For a shared, no-sign-in Chromebook where students actually need to open Helperbird, use a Managed Guest Session.

In short: kiosk hides the browser UI. Managed Guest Session keeps it. If a student needs to click something, you need a Managed Guest Session.

More detail: How to Deploy Helperbird in ChromeOS Kiosk Mode

What a Managed Guest Session Is

A Managed Guest Session (MGS) is a shared ChromeOS session that anyone can start from the login screen without entering credentials. Everything about it is controlled by your Admin console policies.

For exams it gives you exactly what a kiosk gives you, plus extensions:

• No sign-in required. Students click one button at the sign-in screen and they are in.
• Policies are device-level. They follow the Chromebook's organizational unit, not the student, so it does not matter which device a student picks up.
• Extensions can be force-installed. Helperbird installs automatically and cannot be removed.
• Managed JSON policy works. Your subscription key, admin controls and feature restrictions all apply.
• Everything is wiped at sign-out. Browsing data, downloads and cookies are cleared when the session ends, so nothing carries between students.

Which Option Do I Need?

Check this first. If your students sign in to their own school accounts and you only need Helperbird available during assessments, you do not need a managed guest session. Force-install Helperbird for the student OU and it stays available during Google Forms locked mode quizzes. See How to Use Helperbird in Locked Mode on Chromebooks.

Managed guest sessions are for the case where nobody signs in at all.

Before You Start

⚠️ Check your licence first

Managed Guest Sessions require an Enterprise Upgrade or Education Upgrade.

A Kiosk & Signage Upgrade does not support Managed Guest Sessions. If your exam Chromebooks are on Kiosk & Signage licences, you will need to upgrade them before any of this works. This catches a lot of schools out, so it is worth confirming before you start.

Make sure that:

• Your Chromebooks are enrolled in Google Admin as managed devices
• Your exam Chromebooks sit in their own organizational unit
• You have administrator access to admin.google.com
• You have your Helperbird subscription key ready
• You know the Helperbird extension ID: ahmapmilbkfamljbpgphfndeemhnajme

If you have not created an OU for exam devices yet, see How to Set Up a Child Organizational Unit for Helperbird.

Step-by-Step Setup

Step 1: Turn On Managed Guest Sessions

1. Go to Devices → Chrome → Settings → Device settings.
2. Select the organizational unit holding your exam Chromebooks.
3. Find Sign-in settings → Managed guest session.
4. Set it to Allow managed guest sessions (or Auto-launch managed guest session if you want devices to drop straight into it on boot).
5. Click Save.

Step 2: Add Helperbird to the Managed Guest Session

1. Go to Devices → Chrome → Apps & extensions → Managed guest sessions.
2. Select the same organizational unit.
3. Click the + button and choose Add from Chrome Web Store.
4. Search for Helperbird, or paste the extension ID ahmapmilbkfamljbpgphfndeemhnajme.
5. Click Helperbird to add it.

This is the tab that accepts extensions. Helperbird will be added without any error.

Step 3: Force Install

Set Installation policy to Force install.

Helperbird now installs automatically on every device in that OU, and students cannot remove it.

If you also want the Helperbird icon visible in the toolbar, choose Force install + pin to browser toolbar instead. Both options are available in Managed guest sessions, and this is one of the things a kiosk cannot do.

Note: apps and extensions whose Chrome Web Store listing is restricted to your domain cannot be installed in a Managed Guest Session, because nobody signs in. Helperbird is a public listing, so this does not affect it, but it is worth knowing if you deploy private extensions too.

Step 4: Add Your JSON Policy

In the Helperbird settings panel, find Policy for extensions and paste:

{
 "subKey": {
 "Value": "YOUR-SUBSCRIPTION-KEY-HERE"
 },
 "isAdminControl": {
 "Value": true
 },
 "floatingButton": {
 "Value": true
 }
}

Replace YOUR-SUBSCRIPTION-KEY-HERE with your actual key.

floatingButton matters here. In a locked-down session the browser toolbar is often hidden, so students cannot see the Helperbird icon. The floating button puts a Helperbird button on every page instead. See How to Enable the Helperbird Floating Button.

Step 5: Save and Reboot

Click Save, then reboot one of the Chromebooks to pull the policy immediately. ChromeOS otherwise checks for policy updates roughly every 3 hours.

To confirm it arrived, open chrome://policy in the session and look for the Helperbird extension ID and your subKey value.

Exam Settings Worth Adding

Turn Off Features Students Should Not Have

{
 "subKey": { "Value": "YOUR-SUBSCRIPTION-KEY-HERE" },
 "isAdminControl": { "Value": true },
 "floatingButton": { "Value": true },
 "disableFeatures": { "Value": true },
 "disabledFeatures": {
 "Value": [
 "EditorReader",
 "VoiceTypingOptions",
 "ScreenshotOptions"
 ]
 }
}

Feature codes are case-sensitive. Full list: How to Disable Helperbird Features Using JSON Policy.

Turn Helperbird Off on the Testing Platform

{
 "subKey": { "Value": "YOUR-SUBSCRIPTION-KEY-HERE" },
 "isAdminControl": { "Value": true },
 "excludedDomains": { "Value": true },
 "excludedDomainsList": {
 "Value": ["testplatform.com"]
 }
}

The floating button still appears on excluded domains, so students always have a way to open Helperbird. Full guide: How to Disable Helperbird on Specific Websites.

Validate Before Exam Day

Run your policy through the JSON Policy Validator first. A single misplaced comma stops the whole policy applying.

How It Works on Exam Day

1. The Chromebook boots to the sign-in screen.
2. The student clicks the managed guest session button. No username, no password.
3. Helperbird is already installed and already licensed, because the subscription key came through the device policy.
4. The student opens Helperbird from the toolbar, or from the floating button if the toolbar is hidden, and uses their accommodations.
5. At sign-out everything is wiped and the next student starts clean.

No student ever enters a subscription key or signs in to Helperbird.

Troubleshooting

"Selected app is not enabled for kiosk mode"

You are on the Kiosks tab. Extensions cannot be added there. Switch to Managed guest sessions and add Helperbird again, as shown in Step 2 above.

Helperbird is not appearing in the session

• Confirm you added it under Managed guest sessions, not Users & browsers or Kiosks. Policies do not carry between these tabs.
• Check the Chromebook is in the right OU under Devices → Chrome → Devices.
• Confirm Installation policy is set to Force install, not Allow install.
• Reboot the device to force a policy sync.

The subscription key is not applying

• Open chrome://policy in the session and check the subKey value is present and correct.
• Validate your JSON with the JSON Policy Validator.
• Check nothing is blocking us: visit https://engine.helperbird.app/firewall/. If it reports blocked, allowlist engine.helperbird.app on your network.

Students cannot find Helperbird

The toolbar is likely hidden. Add "floatingButton": { "Value": true } to your policy.

The managed guest session button is not on the sign-in screen

Two things to check:

1. Licence. Managed Guest Sessions need an Enterprise or Education Upgrade. A Kiosk & Signage Upgrade will not offer the option at all.
2. Device settings. Managed guest sessions must be enabled under Devices → Chrome → Settings → Device settings → Sign-in settings, and the setting applies per organizational unit. Go back to Step 1.

We are on Chrome App kiosks and something just broke

ChromeOS 150 is the last release supporting Chrome Apps in kiosk sessions. From ChromeOS 151 they stop working. The LTS channel extends this to April 2027.

Chrome Apps force-installed for Managed Guest Sessions and user sessions are unaffected. If an assessment platform you rely on ships as a Chrome App kiosk, speak to that vendor about their migration plan. See End of support for Chrome apps.

Related Guides

• How to Use Helperbird in Locked Mode on Chromebooks
• How to Deploy Helperbird in ChromeOS Kiosk Mode
• How to Use Helperbird in Locked Mode on Chromebooks
• How to Enable the Helperbird Floating Button
• Setting Chrome Storage Managed Keys for Helperbird
• How to Set Up a Child Organizational Unit for Helperbird
• How to Disable Helperbird Features Using JSON Policy
• How to Disable Helperbird on Specific Websites Using JSON Policy
• Verify Your Helperbird Managed Deployment

References

• Managed guest session devices - Google Help
• Use Chromebooks for student assessments - Google Help
• End of support for Chrome apps - Google Help
• Connecting an Extension from a Kiosk PWA - ChromeOS.dev
• Automatically install apps and extensions - Google Help
• Manage Chrome kiosk app settings - Google Help
• Add web apps to Chrome kiosks - Google Help
• View and configure apps and extensions - Google Help

Need Additional Help?

If you have any questions or run into any issues, please contact the Helperbird support team. You can reach us at Helperbird support. We are happy to help you get the most out of Helperbird.