HOW TO USE:
1. Assign your needed urls from addon's options menu.
2. Press ctrl
3. Release ctrl
4. Then press the desired number within a second
I came up with this method because just the number presses were interfering with some editable fields and making it hard to use.
Also, firefox has the default tab browsing with ctrl modifier to switch to tabs positioned in respective number. I guess that cannot be over-riden.
So I came up with this method. I hope you like this new feature..
The name of this application is Spell tab, because as like in MMORPGs you can cast spells through number keys. In a similar way, you now cast spells on the tabs. :) The experience will best be enhanced by a mouse with numpad.