JavaScript to the operating system's API with superuser privileges. These flaws have affected major browsers including Firefox, Internet Explorer, and Safari. Plugins, such as video players, Adobe Flash, and the wide range of ActiveX controls enabled by default in Microsoft Internet Explorer, may also have flaws exploitable via JavaScript (such flaws have been exploited in the past). In Windows Vista, Microsoft has attempted to contain the risks of bugs such as buffer overflows by running the Internet Explorer process with limited privileges. Google Chrome similarly confines its page renderers to their own "sandbox". Web browsers are capable of running JavaScript outside
Safari (web browser) support, which can make JavaScript loading up to 50% faster. It also has built-in crash resistance unique to Snow Leopard; crash resistance will keep the browser intact if a plug-in like Flash player crashes, such that the other tabs or windows will be unaffected. Safari 4.0.4, released on November 11, 2009 for both OS X and Windows, further improves JavaScript performance. Safari was one of the twelve browsers offered to EU users of Microsoft Windows in 2010. It was one of the five browsers displayed on the first page of browser choices along with Chrome, Firefox, Internet Explorer and Opera.