As of Firefox 59, this is in Options

###Open the Options window

###On the left side of the screen, click "Privacy & Security"

###Under the "Permissions" section, find "Notifications" and click the "Settings..." button

###Check the box that says "Block new requests asking to allow notifications"

As of Firefox 59, this is in Options

Open the Options window

On the left side of the screen, click "Privacy & Security"

Under the "Permissions" section, find "Notifications" and click the "Settings..." button

Check the box that says "Block new requests asking to allow notifications"