The best manual of how to use "The easiest Xdebug" addon for Firefox

Installation notes

0. Install the best Firefox add-on for remote debugging The easiest Xdebug. I'm not lying.

1. Install the xdebug extension from PECL or from a repo or download sources to compile it manually:

git clone git://github.com/derickr/xdebug.git
Xdebug downloads page

2. Compile the extension

cd /xdebug/src/path
/path/to/your/phpize
./configure --prefix=/php/installation/prefix --enable-xdebug --with-php-config=/path/to/your/php-config
make -j4
sudo make install

4. Configure Xdebug in your php.ini

zend_extension="/path/to/installed/extension/xdebug.so"
xdebug.remote_enable=true
xdebug.remote_host=127.0.0.1
xdebug.remote_port=10000 (port 9000 is occupied by FPM, but you can set another)
xdebug.remote_autostart=1
xdebug.idekey= (you can just leave it empty)

3. Make sure Xdebug was installed successfully

/path/to/your/php -i | grep xdebug

4. Don't forget to configure your fastcgi-server if you use one (example of nginx server config):

fastcgi_param PHP_IDE_CONFIG serverName=$server_name;

5. Don't forget to reload your web-server or php-fpm.

IDE configuration

Configure your xdebug port (10000 is our case)
Filter external connections if you don't want to accept debug requests from aside
Add server configuration of your site
Go to Run->Edit configurations. Add "PHP Remote Debug" configuration, select your server (that you just added) and enter IDE-key, a string that will filter debug data by debug-session name:

Action!

Select Run->Debug... and select your remote configuration name (as you named it above):

IDE now listens incoming connections on port 10000. (Hey, article writers, do you fucking know that IDE is a server here? Yes, xdebug sends data directly to IDE)
Confgure your addon in Firefox. Go to Tools->Addons->Extensions->The easiest Xdebug and change your IDE-key to selected one.
Open the site page that you want to debug and click the "bug" icon on your Addon Bar. It will become colorized and animated. This means that session name is set and after page reloading IDE will stop at your first breakpoint (in this manual you will not find what it is).

Also there is a usefull page for checking cookies that the add-on sets: http://manual.pohape.ru/xtest/