Tutorial: Using manyCalendars on a Managed Corporate Device

Can you install a browser extension on a company laptop?

The short answer: it depends on your organization's Mobile Device Management (MDM) policy. Some companies allow browser extensions freely. Others lock them down entirely. Most fall somewhere in between, maintaining an allowlist of approved extensions or blocking specific categories.

Before you try to install manyCalendars (or any extension), it is worth understanding what your device allows. Attempting to install a blocked extension will not cause problems, but it will fail silently or show an error, which can be confusing.

How to check your MDM policy

Chrome: Navigate to chrome://policy in your address bar. Look for policies named ExtensionInstallBlocklist or ExtensionInstallAllowlist. If the blocklist contains a wildcard (*), all extensions are blocked unless specifically allowlisted. If no extension policies are listed, you are likely free to install extensions.

Edge: Navigate to edge://policy. The same policy names apply. Many organizations manage Edge more loosely than Chrome, which is why Edge is sometimes the better option on a managed device.

Firefox: Navigate to about:policies. Look for ExtensionSettings or InstallAddonsPermission. Firefox enterprise policies work differently but achieve the same result.

If you see extension restrictions, check whether your IT team allows requests. Some organizations have a process for requesting specific extensions to be added to the allowlist. manyCalendars's minimal permissions make it an easier approval than most.

What manyCalendars needs vs. what it does not

manyCalendars's requirements are unusually modest for a productivity extension. Here is what it needs:

Required: Permission to read specific calendar web pages (Google Calendar, Outlook Web) in your open tabs. Local storage to save your calendar configuration. That is it.

Not required: No admin access to your machine. No API tokens from your IT department. No OAuth connections to your calendar accounts. No background network requests to external servers. No access to your browsing history, cookies, or other tabs.

If your IT team asks what the extension does, the answer is straightforward: it reads calendar data from tabs you already have open and displays it in a unified view. All data stays in the browser's local storage, read and merged on your device, not in our cloud.

Alternatives if extensions are blocked

If your managed device does not allow browser extensions at all, you have two solid options:

Option 1: Use manyCalendars on a personal device. Install manyCalendars on your personal laptop or phone browser. Add your work calendars via ICS feeds (if your organization publishes them) and use your personal device as the unified view. Your work device stays untouched.

Option 2: ICS feeds only. Many calendar systems can publish read-only ICS feeds. You can subscribe to these feeds from any calendar app. The data is read-only and the feed URL acts as the authentication. No extension needed. The tradeoff is that ICS feeds refresh on a schedule (often hourly), so you will not see changes in real time.

Neither option requires any changes to your managed device or any conversation with IT. That is the point. Get started with manyCalendars, and let your IT department keep wondering why you never have scheduling conflicts.