Browser testing can be an annoyance but is necessary due to inherent incompatibilities between Microsoft’s Internet Explorer (IE) and Mozilla’s FireFox, further incompatibilities between different versions of the same browser (mostly IE issues), as well as numerous bugs that were never fixed in some versions. This situation has always existed and started way back when Netscape and Microsoft jockeyed for the top market share position. Each introduced a number of new features that were not always recognized by the other, and both companies were guilty of frequently ignoring the established W3C (World Wide Web Consortium) standards in favor of their own standard-setting desires.

By any measure, Microsoft won the early battles and today Netscape’s browser is nowhere to be found. Mozilla’s FireFox has taken over as the number two browser and has won over a large percentage of users who are concerned about Microsoft’s continual issues with browser security as well as a percentage of the technical users who just dislike Microsoft in general.

Although the situation with browser compatibility has gotten better over the years, there doesn’t appear to be any browser that is fully compatible with the World Wide Web Consortium’s (W3C) standards for HTML, XHTML and CSS. There are even differences between IE6 and IE7 in the way that each browser version renders CSS, and a number of issues between IE and FireFox. It is therefore important to set up a range of different browsers to hanfdle all of yoru testing needs.

Determining which browsers your customers are using

The easiest way to determine which browsers to use for testing is to examine your server logs using whichever log analysis software your hosting company provides. Almost all hosting companies offer log analysis software such as AwStats or Webalizer and you should make sure that any hosting company that you use offers a way to analyze the server logs.

The server log file

Every time a user requests a Web page, the server records the request in a log file. Along with the name of the requested file and other details, the server records the browser type and operating system that is making the request. This information is compiled and displayed through log analysis software. To make sure that your testing covers the browsers your customers use, make a list of the most popular browsers found in the log files.

At one time, there was a greater need to test using a wide range of browsers. Today, the number is smaller and consists of IE6, IE7 and FireFox. If your log file analysis software tells you that your have a significant percentage of Macintosh users, then you also should add Safari to your testing environment.

Installing multiple versions of IE on a single PC

Because Internet Explorer is somewhat integrated with the operating system on PCs using Microsoft operating systems, it is difficult to cleanly install multiple versions of the IE browser. If you need to test with multiple versions of IE, one solution is to install each version on
a separate PC and turn off the automatic update feature found in newer Microsoft operating systems so that the installed version does not get replaced with a newer version. Be aware that this may leave some security holes unpatched, so you should do manual updates on a regular basis, but just be careful that you do not upgrade IE6 to IE7.

FireFox has been much more consistent with rendering issues from one version to the next, so there isn’t a need to install multiple versions.

FireFox can be found at: Mozilla FireFox

What about Macintosh testing?
If your targeted market includes a lot of people with creative talents, you will likly find a significant percentage of Macintosh users. Graphic artists and Web site designers seem to love Apple’s Macintosh computers. Their loyalty is probably the primary reason that Apple continues to exist. But if you use a Macintosh for design work, recognize the cold fact that 99+% of Internet users are using PCs. You will therefore need to test using a PC. There are inherent differences between a Web page rendering on a PC and one on a Macintosh. Colors are slightly
different, images display darker on a PC, screen resolutions are different and the recognition of some HTML tags is different. You therefore absolutely need to test using a PC. Likewise, if you develop Web sites on a PC and your server logs indicate that a significant percentage of your visitors are utilizing Macintosh computers, you should set up a Macintosh with the appropriate browsers for testing.

Apple recently began offering a version of Safari designed for PCs. Apple Safari for PCs.

Remember to clear the cache before testing

Modern browsers cache (store) HTML, images, JavaScript and CSS files and use those files to speed up rendering the next time a page is requested. You must therefore clear the browser cache before you begin each Web site test. This assures that the tester will experience the same rendering performance as a first-time visitor.

Clearing the cache with Internet Explorer:

1. Select Internet Options from the Tools drop-down menu
2. On the General tab, click the Delete Files button
3. Click the OK button in the Delete Files window
4. Click the OK button to return to the browser window
5. Click the Refresh button

Internet Explorer offers an additional feature that clears the cache every time you shut down the browser. To turn this feature on, first make sure the cache is clear using the procedure listed above. Next, select the Tools menu from the toolbar, select Internet Options, select Advanced, and scroll down to the Security section and make sure that "Empty Temporary Internet Files when Browser is Closed" is checked. If you check it, make sure to click OK.

Clearing the cache with FireFox

1. Select Tools on the top menu
2. Select Options
3. Click the Privacy icon
4. Click the Clear Now button in the Private Data section
5. Click Ok
6. Close FireFox and restart it

Browser compatibility testing services

There are a few services–some free and some by subscription–that provide simulations of various browser renderings. These services can be useful for identifying rendering problems due to browser incompatibilities. You can find them by searching for"browser compatibility testing". Here is one popular choice: NetMechanic’s Browser Photo

.