All they really know is that they tested it with IE, Firefox, maybe Opera and Safari, and it seems to work.

他们所真正知道的只不过是他们已经在IE、Firefox，也许还有opera和Safari上测试过，看起来正常而已。

youdao

Each browser needs special code to hook in to triggering the loading of the browser by Selenium, thus an unknown browser (such IE 8, Opera 10, Firefox Nightly, or Chrome) may not be able to run.

每个浏览器都需要特殊的回调代码以让Selenium加载浏览器，这样未知的浏览器(如ie 8、Opera 10、Firefox Nightly及Chrome)可能就没法运行了。

youdao

So instead of getting IE bundled with the OS they were offered IE, Firefox, Opera and so on and were thus not locked in in any manner.

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The service is supported on iOS, Chrome, IE 9, Firefox, Safari, Opera and Roku devices, though those geographic restrictions keep the access pool quite limited.

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