I'd give this 5 stars if it wasn't for the fact the newer versions have switched out the "X" close icon to the ugly tab thing. Otherwise, this is excellent and really should be a stock option in FF.

Alternative button colours would help. Button works fine.

Is it possible to add an option for different icons?
You can see here your addon and old "Close Button" addon that is not compatible with quantum: https://i.imgur.com/13uTZO4.png

Not quite what i am looking for.
Is it possible to code an add-on that closes the tabs from right to left?
1 click > 1st tab on the right side close the tab. 2nd click > 2nd tab on the right close and so on.