I was getting a few complaints that the websites we were working on stopped working on Google Chrome. Which came as a big surprise to me since when I repeated the test on my system and it worked properly. I managed to take a look at one of the users who was having problems and noticed that she was running the latest Chrome Beta with Extensions support. She had already installed a few extensions as well.
Acting on a hunch I disabled all extensions and... the website started working again.
Why was this happening? Well, the extensions/add-ons/plugins you've installed onto your browser (Doesn't matter if it's IE, Firefox or Chrome) have the capability of manipulating and analyzing the page you're viewing so they can do whatever it is they do. And when they DON'T do it properly, they start breaking the pages you're viewing by maybe.... inserting elements of their own, or changing tags and CSS class names of elements? In the age of AJAX where the webpages themselves are heavily running client side code to manipulate the document at the client end this could lead to disastrous results.
I guess the fact that extension support is technically still in Beta for Chrome also adds to the reasons for failure.
While these incidents with the extensions just reinforces my mindset that all web browsers are inherently stable until 3rd party plugins/add-ons/extensions are introduced. I worry about the day where a client will insist that there's a problem with a webpage because it doesn't work with their browser that has a particular extension/plugin/add-on installed.
So, if you had a webpage that was working fine previously before you added that new fangled Firefox Extension or Chrome Extension Or IE Add-On, maybe you might want to turn that particular thing off and try the page again?