Sidebar Google Mail extension for Firefox allows to use Google Mail from Firefox browser’s sidebar.After installing this add-on it shows envelop icon below the URL box which is much popular for Gmail.By clicking envelop icon Google Mail window will be shown in sidebar to login to Google Mail.
Once you signed into Google Mail you can continue visiting other pages in Firefox even if you closed Google Mail sidebar you can reopen it again without logging into Google Mail.You can open /close Google Mail client on your sidebar by clicking envelop icon or pressing Alt+G.
A green envelop will be shown below the address bar for Sidebar Google Mail extension a red envelop shown always indicator that you have unread email.
You can install this extension by opening it and navigating to Firefox located in program files , as normal installation doesn’t worked for me.
This add-on not worked for me shown IMAP connection error.