Hi, open the 3-bar menu > Customize, and if you can see the button, simply drag it to a toolbar and the location of your choice, then Exit Customize to save. If the button isn't there, try clicking on Restore Defaults. More here - Customize Firefox controls, buttons and toolbars.

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Thank you for your reply. I apologize if I was misleading on my question. What I am now missing is the envelope icon that allowed me to go directly to my inbox to view my email and then perform tasks to forward, or reply. What I received in response to my initial question was a link.

If you can show me how to access my yahoo email through Firefox like I had, it would be appreciated.

Mike Brooks

Thank you for your reply. I apologize if I was misleading on my question. What I am now missing is the envelope icon that allowed me to go directly to my inbox to view my email and then perform tasks to forward, or reply. What I received in response to my initial question was a link.

If you can show me how to access my yahoo email through Firefox like I had, it would be appreciated.

Mike Brooks

Firefox doesn't have an email button by default. If you had one it may have been a bookmark or a toolbar button that was added by an extension. In the Add-ons Manager, do you have any extensions that are disabled? "unsigned" extensions were disabled with the Firefox 43 update.