Debugger; keyword

From FirebugWiki

To stop script execution at a specific line inside your code you can use the debugger; keyword. As soon as this line is reached, the execution is halted, Firebug switches to the Script Panel and a break notification is shown. Break notifications can be disabled by unchecking the "Show Break Notifications" option inside the Script Panel's Options Menu.

Example:

  function test(variable) {
    for(var i=0; i<10; i++) {
      if(i == 5)
        debugger;
    }
  }

[edit] Discussion

• On breakpoint markers: http://groups.google.com/group/firebug-working-group/browse_thread/thread/6dece6d4300c971b