Debugging browser extensions

Question

Opera

Is there any special utility or something else for developing / debugging browser extensions? Or stupidly wrote a line, installed, checked, deleted, and so on in a circle?

Answer 1

FF - developer.mozilla.org/en/Setting_up_extension_development_environment
Chrome - code.google.com/chrome/extensions/tut_debugging.html

Answer 2

Under Chrome - a built-in debugger, under the rest, obviously, the same.

Answer 3

Under Firefox - Chromebug like