Useful browser addons for QA

With so many browsers to choose from nowadays, it's important to choose the right one.

For me, the wide array of add-ons that are available to aid my day to day job, definitely play a part in my choice. I choose Google Chrome, having an Android phone, means I can sync my favourites between my Mac, my phone and my work PC (100% personal reasons! There are some professional reasons below!)

There are also a wide array of add-ons that Chrome supports that helps make my life easier, and I strongly recommend any QA have when testing a web UI.

These are the ones that I use on a regular-ish basis:

Fiddler - not really an addon for Chrome, but essential in monitoring HTTP requests and responses. It enables you to change requests/responses by setting breakpoints etc. Fiddler in itself could and one day will have a whole blog post about the benefits and the uses and how it can aid with testing. 

Fiddler can be downloaded from here

FireBug - This is essential. I can not understand how a browser can not have this addon installed! It's so powerful in investigating bugs. Here are just some of the things you can do with Firebug:

• Editing and Monitoring CSS and Javascript - Using firebug you can edit css on any live html page, which is nice to do when some formatting isn't quite right, you can investigate why and even add to the bug how it can be fixed :) As for Javascript, being able to monitor javascript calls during the loading of a web page can save a lot of time, you can even investigate javascript errors using Firebug if you feel comfortable enough!
• Helpful in automating tests as it allows you to view the element information that you'll need for interacting with the page when writing automated tests.

Firebug can be downloaded from here

Y-Slow - This is an extremely useful tool, it grades the webpage, and is extremely useful in suggesting possible improvements for sitespeed and validating the source of the page. 

YSlow can be downloaded from here

Modify HTTP Headers - This is a firefox only addon, although there are similar tools for Chrome. This allows you to change the headers to alter website behaviour. I have personally used it so the website under test thinks I am visiting the site from another location, so it is definitely useful when testing international websites.

Can be downloaded from here

ScreenGrab! - This is useful when raising bugs! You can get it to take a screengrab of the entire webpage, not just the visible portion of the screen. 

Can be downloaded from here

Spoons.net - Not really an addon, but extremely useful cross browser testing tool, that enables you to test on any of the latest browsers. If you wish to test on legacy browsers, then a pro account is needed (£££)... It's free to sign up and test on the current versions of browsers :)

Can be viewed here

Ghostery - Useful addon for seeing what affiliates and what tags are fired on your website. Can be downloaded for any browser. Makes testing things like webtrends and Google Analytics a lot easier!

Can be downloaded from here

Feel free to leave a comment of anymore plugins that you find useful and why!