Test the look of your Web site in different Web browsers without installing all the different browsers. Use a Web browser emulator.
Some Web browser emulators load a real browser, capture a screen shot, then display the screen shot or email the screen shot to you. Some emulations use different browsers with special settings to emulate the browser you request and may not produce exactly the same result as the real browser.
You might be presented with the choice between version 5 and version 6 of a browser but major changes might have occurred in 5.5 or in 5.0.3. When you check the results against a compliant from a customer, you need to get the exact version they use.
Microsoft Internet Explorer has a
quirks mode and some other browsers have an equivalent. When a browser operates in
quirks mode, the browser makes guesses about what the Web site might be doing then changes the result based on the guess and the page no longer looks like what you would expect. The default might be quirks mode off but a complaining customer might have quirks mode set to default on. The variations are endless. One version of Internet Explorer appeared to be 4 MB of browser and 28 MB of quirks.
Internet Explorer is, again, the worst case here. IE has profiles with weird mixtures of settings in each profile and nothing to tell you exactly what is set in each profile. You customer can see wildly different results based on the profile they select.
A minor maintenance update to a browser might make major changes to the settings, profiles, quirks mode defaults, anything, and everything.
Browser Shots, from browsershots.org, have a wide range of browsers ready to use for free. You select what you want, enter your URL, then wait from a few minutes to an hour or so. You can pay per month for priority access.
The free test does not present any processing options. One browser failed because it asked
Do you want to accept a cookie?
, a question you cannot answer in the free test.
The test page contains a Google map and several browsers failed to display the map. You could use a module to detect the browser then display a static image instead of the Google map.
Browser Shots links to crossbrowsertesting.com where, for a monthly fee, you can test with more browsers including mobile phone (cell phone) browsers. $19.95 gets you 150 minutes of testing per month including hands on use of the browsers, letting you accept cookies, log in to your site, and do all the other things you cannot do in Browser Shots. CrossBrowserTesting is a good investment for professional Web developers working on new themes.
The test page contains a Google map and several browsers failed to display the map. You could use the online testing to test alternatives to the Google map.
Browsercam, www.browsercam.com, offers a range of browsers and mobile devices with a free 24 hour trial. CrossBrowserTesting competes against Browsercam and you would have to try both to pick your choice. The Browsercam trial is only 24 hours so pick 24 hours when you have plenty of time for testing and some tricky tests lined up.
NetMechanic, www.netmechanic.com/products/browser-index.shtml, offer another paid service named Browser Photo but it appears to offer fewer choices than Browser Shots. I have not found a reason to use NetMechanic.
You can download old browsers from various archives including browsers.evolt.org. You need all the right operating systems. Some browsers let you install multiple versions at the same time while others fight each other. You will most likely need a virtual machine environment to use all the operating systems on one machine. This get messy really fast and, at the end, you do not have browsers for all those hand held devices including mobile phones. $19.95 for a few hours testing against many browsers suddenly looks great.
You can install multiple versions of Firefox and other popular open source browsers side by side without them crashing into each other. Set up what you need then look to the alternatives.
I suggest testing with the free Browser Shots and avoid installing the browsers they provide. Then you buy an Android phone. If you have several people on the same project, one will have an iPhone. Someone might have an ancient iPhone 3 or earlier. You can eliminate a lot of the important tests then choose the next step.
Now look at the paid online services offering whatever you do not have.
If you use only Linux, you will not have Windows but one of the people on your project probably has a notebook computer with Windows. You can install some versions of IE on each release of Windows and installing more than one version is a painful task. You will need several Windows machines or a machine split up with virtual machine software, and be prepared to waste a lot of time. After you make your Web site work in every other browser, killing the Internet Explorer problems will take hours and more time than the Browser Shots service offers for free. The $19.95 service will not have enough hours. You will need the next service up. Fortunately you can pay for just one month then not pay for the months you do not use, making CrossBrowserTesting and equivalents far cheaper than wasting hours on setting up multiple releases of Windows with multiple versions of internet Explorer.