[dathinab]

I think the following two fact that played a big role in it:

1) Microsoft has another "official" browser

2) Chrome "eats the world", many people use it at home and many sites only officially support chrome. In many ways chrome has become the new IE. (Sites relying on non standardized Chrome specific quirks and being broken on other browsers, especially if they are not at least partially chromium based.)

[cezart]

I recently got actually burned by this. I was implementing the redesign for a friend’s website. I was working in Firefox, cause that’s the browser I want to support. The page seemed pixel perfect to me. Then my friend told me there was a subscription form he didn’t want at the bottom of the page. What was my suprise when I found out that there was an entire partial with an html error in it, that I missed in code, which was rendered in Chrome, but it was not rendered at all in Firefox.

[drewzero1]

I've been a Firefox user since version 2 and experienced this kind of thing early on.

Years ago I was making a GeoCities page and thought it would be a great idea to add a little picture/icon that followed the pointer around on the webpage (because that was a "cool feature" offered on the site builder at that time). I couldn't get it to work no matter which picture I tried, and I kept trying to add them many more times before eventually giving up on it.

Some time later I wanted to show off the site to a family member on their computer. I pulled up Internet Explorer (because they didn't have Firefox) and navigated to my webpage, where I was greeted by a swarm of icons following the pointer around and slowing the whole computer to a drag.

Lesson learned, test on multiple browsers because people will probably view your site in multiple browsers.