How can I change the color of the open tab in Firefox?

Question

The newest version just indicates which tab is open with a little "x" - which, for me, is difficult to see when I have lots of tabs open.

Answer 1

Use the Tab Mix Plus addon, and in Tools, Tab Mix Plus Options, click Display, click Tab and check the box that says Current tab. Now click Customize Styles and under Current Tab select how you want the current tab to be displayed (e.g. background colour of Red). Click OK and OK again.