GMail Checker


Firefox extension to check for new mail in your Google Mail and Google Apps (Gmail for Domain) accounts.

Upon first installation, the button is likely to be placed in your 'Customise Toolbar' window. You need to open this window (View/Toolbars/Customise...) and drag it onto your preferred location in the main toolbar.


1. Does it work with 2-step verification?

Yes, you need version 2.6 or above.

You need to generate an application-specific password ( for Gmail Checker for each of your accounts which use 2-step verification. This password must be saved locally in 'Manage Accounts'.

This means that you need two passwords (one is your actual password, the other is the application-specific password) to check mail in this type of account.

2. My account keeps being logged out when I open the mailbox or open a message

There are 2 probable causes:

* You've opened different accounts side by side, i.e. on different tabs or windows.
* You've selected 'Sign out' on Gmail website.

Doing either of those will invalidate cookies currently used by the extension for authentication. This is an expected behaviour and not a bug, so there won't be a fix.

If you encounter this problem, you need to select 'Log out' of that account from the extension's menu to remove all invalid cookies.

You don't need to log out of an account to open the mailbox of another account. Just close its tab or window first and then open the other account.

3. My account failed to log in, or the extension shows incorrect mail number

This problem cannot be solved without a debug log regardless how detailed you try to explain.
Open the Debug Window in 'About...' and then log in to the account again to get the debug log.

4. I don't want to save my account's username and password locally.

You don't have to. Just select "Log in to new account" in the menu and enter the account you want to check mail.

5. What does "Remember login cookies" in the login window mean?

It means that authentication cookies won't expire after you've closed the browser.

Tick this check box if you want to reuse your authentication session when Firefox reopens without storing your username and password locally.

6. Where are the settings and account details stored? How to back them up?

They are stored in a file called gmailchecker.sqlite under your profile directory. The passwords are encrypted using Firefox's built-in password manager and may not be decrypted on another machine (I don't know?). So the file may be unusable on the other machine.

7. Is the locally saved password encrypted?

Yes, in the same way as the passwords stored by Firefox's built-in Password Manager.

8. Where is 'Log out of all accounts'?

It's under each account's submenu.

9. I've got more than 20 new mail but it shows only 20?

The extension uses Gmail Atom feeds which have a limit of 20 messages. This is not a bug so please do not ask me to fix it. Submit your request to Google instead.

10. How to disable localisation?

On 'about:config', change the value of general.useragent.locale to en to show text in English.
You need to restart the browser for this to take effect.

Download files:


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