Log into multiple Gmail accounts on Firefox

I am sure a many of you have Gmail accounts and if you frequent internet a lot you might have two or even Gmail accounts. Sometimes for a backup, sometimes to keep work and personal related emails separate majority of us might have two Gmail accounts. For instance I have two accounts, one was a personal one, the other I use for testing purposes, like I used it during this post.
If you have two Gmail accounts and need to use them often it can be a bit of a bother considering when you sign-in with one account you cannot sign into the another account on the same browser.
Recently I used another method by using a Firefox add on for using two Gmail accounts at the same time. For using this add-on you need to have Greasemonkey installed on your Firefox browser. If you are using Windows with Firefox you can install Greasemonkey from here.

Google Account Multiple Login

• Gmail Multi User Login works only after you have installed Greasemonkey.
• Download the add-on by clicking here.
• The add-on is installed and you can use Gmail multi user login.
• Once this add-on is installed on Firefox it replaces the Sign-Out link to the right hand top corner of your Gmail account with a drop which allows you to log into another Gmail account.

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