Bug checking is easier more than you may have thought.
So please don’t make it hard on yourself, especially if you are a web developer . . . .
#1. Blank page.
Most of this trouble because some fatal errors but on your live site / shared hosting turned off display errors so you can’t see it. Just turn on it than you can find out it.
#2. Good
development env.
Most of guys here using XAMP / WAMP or etc.Ya it’s okies for starting but as developer i don’t think we should use it for checking / development.
I suggest to use Ubuntu with xdebug ( and of course turn on display errors in ALL ). In this case not only bugs also can help you find out any troubles on your site and you can follow it to trace up.
I always do this way. VMWare with Ubuntu and use it for working, checking, anything
#3. Trace up.
Development or bugs checking is a chain of check and failed and success. It’s mean you’ll try any case you think to find out troubles. Just remember, we are in Joomla. So just follow MVC than it’s okies for almost case.
#4. Ajax checking
Just check w/ Firebug console to find out how do ajax called than you have point for tracing.
Easy huh ?.
Still more but … just keep on your mind: As developer we should try to make processes as simple and efficient as possible.
Thank you
Viet Vu